Keep the faith, don’t lose your perseverance and always trust your gut extinct.

Paula Abdul, Performer

I always trust my gut reaction; it’s always right.

Kiana Tom, Television Host

Intuition comes very close to clairvoyance; it appears to be the extrasensory perception of reality.

Alexis Carrel, Nobel Prize Winner (Medicine)

Before making a decision about whether to trust our gut, it seems like a worthwhile endeavor to first try to understand what exactly our “gut” is. There are a number of possibilities:

1. Sometimes gut feelings can be explained by our evolved instincts that are encoded in our DNA, which exist because they helped our ancestors survive in the world as it was hundreds of thousands of years ago. For example, we are likely to feel anxious when confronted with something unfamiliar (a large unknown animal, for example), or feel fear when we hear a loud noise. These sort of reactions are very useful at times, but typically only work well in scenarios involving danger or conditions that are similar to those that our prehistoric ancestors encountered. At a birthday party where balloons are being popped, a fear of loud noises is not useful. On the other hand, when walking in a canyon, a loud noise might indicate a cascade of rocks and a fear response might save your life.

2. In many cases our intuition is associated with our immediate emotional responses to stimuli. For example, we might get a positive feeling towards someone who has a warm smile, or feel negatively towards a person who is raggedly dressed. While our emotional responses clearly are important (e.g. it’s important to feel sympathy towards a friend when they look sad, and to feel fear when encountering someone who has hurt you in the past) they can also be distorted and counter productive. For example, many people feel slighted if a friend fails to return their phone call. However, one is likely to feel better about the situation (despite his initial emotional response) if he reminds himself that there are all sorts of reasons that a friend doesn’t return calls, including being temporarily busy or absent minded. On the other hand, those who trust in their initial response of hurt and anger (which might stem, for example, from a lack of confidence or insecurity) are more likely to blow up at the friend or act coldly during the next encounter, which could damage a generally fulfilling relationship. Unfortunately, it can be tricky to differentiate between emotional responses that are useful and improve our lives, and those that are based on misperceptions and are unhelpful. Both of these types of emotional responses feel equally real when you are experiencing them, and it is often only when we carefully scrutinize them from a neutral point of view that we can tell the difference.

3. Sometimes our “intuition” is based on repeated experience that we access automatically. For example, a surgeon might get an uneasy feeling during an operation, which could be triggered automatically when she notices similarities between the current patient and difficult surgical cases she has had in the past. Another example would be a painter who suddenly has an impulse to add more thinner to the paint he is using, which could be a subconscious reaction based on years of art making experience. Generally when we repeat similar tasks enough times, their execution becomes automatic and begins to feel like an instinct. We might then say that we have developed an intuition for effectively completing the tasks. These kinds of responses can occur much faster than those controlled by conscious thought, and thus can be very efficient and useful. Of course, if the initial learning phase that leads to one’s intuitions is not of good quality (e.g. we complete the task poorly while learning), the intuition will be of poor quality as well. Sometimes intuitions of this form are experienced in emotional form as an uneasy feeling, in particular when our (possibly subconscious) expectations (based on experience, training or practice) do not match what we see. A day trader, for example, might decide to sell a stock due to an uncomfortable feeling about it. In reality, what may have happened is that the stock chart had a pattern that did not conform to his expectations. This intuition can be quite useful since those cases that don’t match our predictions can be especially difficult, require special attention, and present unknown hazards.

4. Societal conditioning can create a kind of gut reaction that operates without conscious awareness. If we are told enough times when we are young not to trust strangers, then we may feel immediately distrustful when a stranger strikes up a conversation. The trouble with responses of this kind is that they are often formed without thought or careful reflection. For example, if we grow up in an area where a lot of racism is present, we might be told that certain races are inherently dishonest, and so could have strong intuitive reactions to people of those races based on this idea. Similarly, if we are taught to believe that black cats bring bad luck, we might start feeling uneasy in a house with a black cat. Since the ideas that society conditions us with may not be true, it can be very valuable to be aware of these automatic reactions and to carefully evaluate their logical and empirical validity.

5. Our brains are capable of forming very strong associations (between perfumes and people, for instance) and this can lead to what might be interpreted as “gut feelings”. For example, if we were attacked by dogs when we were young, we may feel anxious around dogs later in life, even when we know on an intellectual level that we are safe around them. Such associations clearly have a valuable survival purpose, but on the other hand, can push us into self defeating behavior (like refusing to visit the house of a friend because she has a dog). Our brain’s natural tendency is to be “better safe than sorry”, as your ancestors were very unlikely to die from forming spurious associations (such as that dogs are generally dangerous), but were at real risk of dying if they failed to form certain real associations (such as that wolves are dangerous).

As we can see, what people call their “gut” is most likely a hodgepodge of various brain activities, which include survival instincts, emotional responses, automatic recall of learned information, societal conditioning, and associations. It is not at all obvious that these systems will lead to good decision making in general. Each has its very important uses, as well as significant domains where it will fail. A business man cannot rely on fight or flight instincts when giving an important presentation, a person with an anxiety disorder cannot expect his emotional responses to be accurate representations of reality, a doctor cannot rely on his old impulses when learning a totally new surgical technique, and no one can expect that their society will condition them only with true information. Hence, to make truly good decisions, it is essential to evaluate your intuition to make sure that it is likely to be accurate in the situation at hand. Each time our gut tells us something, we cannot know whether to trust it until we understand where that feeling originates from.

1. Do terrorist groups want to nuke the United States?

It seems that yes, there are groups that would be willing to do this. According to the Report of the Commission on the Prevention of WMD Proliferation and Terrorism, “At the moment, al Qaeda is judged to be the sole terrorist group actively intent on conducting a nuclear attack against the United States.” Of course, it is impossible to rule out the possibility that other groups are also seeking to do this. I’m going to work under the assumption that Al Qaeda and those groups tightly connected to it are the only ones that would have the interest and/or capabilities of actually plotting such an attack at this time.

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2. Where would terrorists get nuclear weapons?

Genuine nukes of great destructive power are quite difficult to build, and cost estimates for building full scale weapons (of the 25-35 kiloton variety) seem to be > $5 Billion. Furthermore, such weapons would likely take longer than a decade to build from scratch (though these numbers are a bit old, so the process may have become cheaper as technology has progressed). Hence, it seems highly likely that if terrorists intended to use such a weapon they would steal them, buy them, or get them through strategic arrangements with governments that already have them. Of course, different types of weapons with different yields would have different costs associated with them, and the amount of time that it would take for construction depends on the scale of the project (with more resources and more scientists it would likely go faster). Some people fear that there may be poorly controlled nuclear weapon materials in Russia (such as bomb-grade uranium). Others fear that nukes could be stolen from Pakistan, in part because of the country’s potential instability, and also because it is possible that Al Qaeda conducting operations there. Iran also could be a potential source of danger, in part because it is run by a religious zealot and it is unclear how far he would be willing to take his anti-American sentiments.

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3. What sort of weapons would terrorists be likely to use?

It would be far, far easier to attack the U.S. with a dirty bomb (a conventional bomb laced with radioactive material such that the material is spread by the blast) than with a full scale nuclear weapon since dirty bombs are so much easier and cheaper to construct or acquire. Such an operation would also seem to have a much greater chance of succeeding than use of a true nuclear bomb since it does not require recruiting high level nuclear scientists, massive payoffs to large nations for supplies, and a laboratory which must be kept secret for a decade or more. The supplies for the construction of dirty bombs are relatively easy to obtain, though these weapons have far less destructive capability than true nukes. There has been at least one known plot (in actuality, probably more like two or three) to detonate a dirty bomb in the United States.

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4. If terrorists did choose to attack the United States with nuclear weapons, how likely would they be to choose Manhattan as their target?

It seems quite likely that if terrorists attempted a nuclear attack on the United States, it would be carried out in either Manhattan or Washington DC. Manhattan is an obvious choice because the County of New York is the most densely populated county in the country, so damage and chaos could be maximized , and because Manhattan has enormous importance to the U.S. economy. DC is also a natural choice because of the opportunity it might provide terrorists to disrupt government operations. That being said, the united states is a huge place, and it is possible that for logistical reasons terrorists might find New York difficult. If I had to put a probability on it, I would guess that there might be a 3 in 10 chance that Manhattan would be chosen as a target.

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5. If terrorists attacked Manhattan with nukes, how bad would it be?

The worst case scenario pretty much would be the detonation of a nuclear bomb (hidden in a truck or in an ocean shipping container). One source (a report by Ira Helfland, head of emergency medicine at Cooley Dickinson Hospital) estimates that a 12.5 kiloton bomb of this nature “smuggled into the port of New York aboard a shipping container and detonated at ground level” would end up killing approximately 260,000 people (about 52,000 of them would die immediately as a consequence of the blast, 10,000 would die soon after from direct radiation exposure, and the remainder would die from nuclear fallout). The study says that that several hundred thousand more would become sick from radiation sickness. There are about 1.6 million residents in Manhattan, which balloons to about 3 million during the day from people traveling into Manhattan. If we assume that the attack occurred during the day (when population densities are highest), and that in total 600,000 either die or get very sick, and that about 2.5 million people are in Manhattan at that moment (since some commuters will have left before the moment the attack occurred, or not arrived yet), then you would have about a 25% chance of dying or becoming seriously ill.

What about the case of a dirty bomb attack? In this case, its that most likely fewer than 10,000 people would die or become seriously ill, leaving a probability of less than 0.5% of sickness or death.

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6. What have known terrorists plots on the united states been like?

Since 9/11 muslim extremists have concocted at least fifteen thwarted plots to carry out terrorist attack in U.S. In fact, the true number is probably quite a bit higher than this. The plots that I was able to find by conducting a few quick searches were:

-Shoe bomb in plane.

-Attempted construction of a dirty bomb.

-Blowtorches to collapse brooklyn bridge.

-Attack New York Stock Exchange and construct a dirty bomb.

-Bomb subway station Near Madison Square Garden.

-Assassinate diplomat with grenade launcher.

-Attack national guard facilities, synagogues and other places in Orange County, CA.

-Plot to blow up wyoming natural gas refinery, the transcontinental pipeline, and the NJ Standard Oil Refinery.

-Potential planned attack on the U.S. Capitol and World Bank headquarters.

-Blow up Sears Tower and FBI offices.

-Attack underground transit links connecting to New Jersey.

-Blow up ten commercial airliners.

-Attack U.S. Army base Fort Dix in New Jersey with assault rifles and grenades.

-Blow up jet fuel artery that runs through residential neighborhoods at JFK international airport.

-Attack the Empire State Building and U.S. nuclear power stations.

Note that all of these attacks have been thwarted, either by the incompetence of the perpetrators, or by effective government work. The only “successful” attacks since September 11, 2001 (that might potentially be considered terrorist attacks) that I managed to find in my quick searches were:

-An Egyptian gunman opens fire at an El Al ticket counter in Los Angeles International Airport, killing two Israelis before being killed himself.

-Joel Henry Hinrichs III detonated a bomb near the packed football stadium at the University of Oklahoma in Norman, Oklahoma killing himself in the process.

-Mohammed Reza Taheri-azar, an Iranian-born graduate of the University of North Carolina at Chapel Hill, drives an SUV onto a crowded part of campus, injuring nine.

-An Afghani Muslim hit 19 pedestrians, killing one, with his SUV in the San Francisco Bay area.

-A man attacks Fort Hood with guns, shooting 44 people.

Something to notice here is that most of these attacks on the U.S. since 9/11 have failed or were foiled, and most of the ones that haven’t failed were relatively small scale. What’s more, all of the attacks listed are much, much less complex and difficult and expensive to pull off than building/acquiring, transporting and detonating a full scale nuclear bomb.

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7. What is a rough estimate of the probability that a person living in Manhattan will die or become seriously injured/sick by a nuclear weapon attack within the next ten years?

This estimate will of course be very crude and inaccurate, but here goes. First lets consider the case of a full nuclear bomb attack. If such an attack occurred in the U.S. and went according to plan, there might be something like a 3 in 10 chance that it would target Manhattan. The chance of death or serious injury depends a lot on the strength of the bomb, but if we assume a large bomb of about 12.5 kilotons this might give a person in Manhattan a 1 in 4 chance of avoiding serious physical harm. What would the probability be that such a plan would be foiled by the government or botched by the perpetrators? The odds seem very good of this happening, as a great number of much simpler attacks that would involve many fewer people have failed. In fact, only about 1 in 5 of the attacks I managed to find information about succeeded, and the ones that DID succeed were some of the very simplest to organize. I would guess that the odds of the success of a full scale nuclear bomb attack are something like 1 in 100. If this seems low, keep in mind that this figure has to take into account the odds that the terrorists fail to acquire or build the bomb despite their attempts, that they run out of funding, that their facilities are discovered and raided, that their bomb is discovered during transportation, that their bomb fails to detonate, that members of their team lose their nerve, that they can’t get the bomb into the U.S., etc.

The next thing to estimate are the odds that SOME terrorist group is actually attempting to plan an attack like this. The plot would be very difficult and expensive to pull off, but on the flip side, would be massively effective at injuring the U.S. (through death, illness, property damage, and widespread panic), so the difficulty might be balanced to some degree in the terrorists minds by the potential damage caused. The enormous potential cost of this project and the expertise required may well be prohibitive though, so I’ll place the odds that Al Qaeda or a closely linked group would pursue completing this project within the next ten years rather arbitrarily at 1 in 10. Here I am assuming that only Al Qaeda terrorist group would even be willing to attempt such a project. All in all, this very crude estimate indicates that the likelihood that terrorists attempt to attack the U.S. with a full scale nuclear bomb, actually succeed in this plan, carry out this attack in Manhattan, and kill any one particular Manhattan resident (chosen at random) is about 1 in 13,300 (over a ten year estimated period). To put this in perspective, the chance that you eventually die of a car accident (rather than other potential causes of death) is about 1 in 6,800.

On the other hand, dirty bomb scenarios are far more likely to be carried out successfully, and far more likely to be attempted (in fact, they already have been) but are unlikely to actually kill or seriously harm a randomly selected person in Manhattan. We can estimate that, once again, there might be a 3 in 10 chance that such an attack (if it occurred) would occur in Manhattan, that if it did happen in Manhattan each individual would have less than a 1 in 200 chance of incurring serious harm (let’s say for the sake of argument that the most likely number is something like 1 in 400), that such an attack might be planned twice in the next 10 years, and that the chance of success for such an attack might be 1 in 10. These give us odds that a single, predetermined person in Manhattan would suffer serious physical harm from a dirty bomb at about 1 in 6,600. This number is also on the order of the chance of eventually dying from a car accident.

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8. How much should we fear nuclear terrorist attacks if we live in Manhattan?

From the simplistic analysis carried out above, the answer seems to be that Manhattan residents shouldn’t fear nuclear terrorism all that much more than a randomly selected American should fear car accidents. One thing that may be worth pointing out is that even if a nuclear weapon did kill us, there is some chance (dependent on the characteristics of that weapon) that it would do so fairly instantaneously, meaning that we would be dead before having much opportunity to suffer or even notice, which seems a lot less horrible than a slow death by radiation poisoning. On the flip side though, if a nuclear weapon was detonated and did not kill or injure us, the psychological effects of such a disaster could still be great, potentially causing the death and injury of those people we know, and likely inducing panic.

While nothing is known for certain and this analysis is certainly flawed in a handful of ways, the chance of a nuclear terrorist threat does not seem high enough to warrant moving out of Manhattan if you derive significant value from living there. Moreover, if you have already decided that you are going to live in Manhattan, what is the use of worrying about death from nuclear weapons at all? It isn’t as though worrying is likely to make you safer in a significant way. There are many things that have the potential to kill us each day, and we tend to simply not think about them, so why should this be different? Sure, it seems scarier in some ways than car accidents, which feel more familiar, but car accidents (and tumors and strokes) can be just as horrible as death by nuclear bombs or dirty bombs. Living in fear will almost certainly reduce your quality of life without making you substantially safer, so the best thing is probably to learn to be okay with the fact that we will never be totally safe (from nukes or cars or the huge number of other things that might hurt us), and this is just a part of life.

If thoughts about nuclear weapons are something that you find you are upsetting yourself with frequently, you might try writing down answers to the following questions:

a) If I don’t worry about hundreds of other potential sources of death, then why should I worry about this one source, especially since it is quite unlikely to occur?

b) What advantages and disadvantages are there to my worrying about nuclear bombs (especially taking into account the fact that there is nothing I can do to prevent such an attack)?

c) Since death is inevitable, and often painful and unpleasant, is dying from nukes really such an especially horrible way to go?

d) What is a more productive use of our time, worrying about nuclear bombs or researching and implementing ways to mitigate preventable sources of death? (keeping in mind that most of us could eat healthier, exercise more, wear our seat belts more scrupulously, get more regular checkups, and do many other things that would likely extend our lives).

Almost nothing can be known for certain. For example, we cannot prove with absolute, one hundred percent certainty that what we take to be “real life” is not just some computer simulation being applied to our brains (like in the movie the Matrix). But, just because we cannot have 100% confidence in much of anything does not mean that we can’t make claims about the world. For example, I can state with a great deal of confidence that there is not an invisible, inaudible, intangible pink elephant in my room. I certainly can’t prove right now that this elephant doesn’t exist, but that doesn’t mean that I shouldn’t say it doesn’t exist. When we have no compelling evidence for a claim, even in the case when we can’t actively disprove that claim, it is generally reasonable to say that we don’t believe in it. Many atheists have similar feelings about the existence of gods. While they cannot prove absolutely that there are no gods, they find the evidence for the existence of gods lacking. Therefore, they say they do not believe that gods exist, just as you would say that the invisible pink elephant in my room doesn’t exist, despite the fact that you can’t actually prove it. As has been pointed out many times before, religious people generally deny the existence of the gods of other religions that contradict their own. Atheists take this one step further, and deny that there is sufficient evidence to believe in any god.

2. Since we are made of energy and the laws of physics say that energy cannot be destroyed does that imply that a part of us must survive death?

While it is true that our energy will never be destroyed, this says nothing about our chances of surviving death or experiencing an afterlife. Think about it this way: If you were to lose a hand, while the energy in the hand would not be destroyed, you would no longer control that hand and the energy in it would then be useless to you. Likewise, when we die the energy in our bodies remains (for a little while, anyway) but this energy is useless to us because our brain, now also dead, can no longer use it to do anything. It is also worth keeping in mind that throughout your life you constantly gain and lose energy from different sources (you lose heat energy through the air, you gain molecular energy from food, you lose molecular energy through waste products, and you convert potential energy into kinetic energy when you move). We are not the same as our energy, energy is just something that we use, and it keeps entering and leaving our bodies throughout our lives.

3. The stuff we see on our planet, like eyeballs and walruses, seem like they were designed to serve a purpose. Does that imply that they must have been created by an intelligent, conscious designer? If we found a watch on the beach we would assume it was designed, so should we assume the same thing about other apparently designed objects?

While eyeballs and walruses certainly appear to be designed, that does not imply that they actually were designed. Until the 1800’s human beings were simply unaware that any naturally occurring process could create something of such enormous complexity and apparent design. However what Charles Darwin discovered is that through a process of “evolution”, it is possible for incredibly complicated creatures to arise from less complicated ones via a combination of random mutation and natural selection. Today, scientists have an enormous body of evidence demonstrating that evolution is true, and hence that creatures that appear to be designed need not ever have had a designer. While evolution doesn’t create things like watches, over incredibly long stretches of time it does create complex creatures which themselves can create watches. The theory is not by any means obvious (which helps explain why it took humans so long to think of it), and if you are incredulous that evolution could possibly work or that enough time could have elapsed to produce all of the complexity we see, I urge you to take the time to educate yourself about the evidence for evolution, and the mechanisms by which it works. Unfortunately, popular attempts to “refute” evolution often are carried out by people who don’t really understand the theory themselves, and therefore these attempts help perpetuate common misperceptions, such as that evolution claims that single celled organisms appeared “by chance” or that evolution makes claims about the way things “should” be (rather than just the way things are and were). Even the evolution taught to children in school is often a highly incomplete explanation of the theory. The best sources for information are books by well respected evolutionary biologists. Without reading any of these it is unlikely that you will truly understand the details of the theory. At this point evolution has as much supportive evidence behind it as nearly any scientific theory.

4. If we don’t believe in certain religions and they turn out to be true, then we will go to hell. On the other hand, if we do believe in a religion, and it turns out that there is no God, nothing bad will happen to us. Therefore, isn’t it the safer bet to take “Pascal’s Wager” and follow a religion just in case it turns out to be the real thing?

To begin with, this question assumes that we can choose what we believe. As far as many religions (such as Christianity) are concerned, just pretending to believe in order to save yourself from damnation probably isn’t going to lead to salvation. On the other hand though, perhaps if you did try practicing a religion intently enough and spending time only with people of that religion you could eventually get yourself to believe if you already were inclined toward spirituality. In that case, which religion should you choose? Should you be a Christian, Muslim, Hindu, Confucianist, Buddhist, Sikh, Spiritist, Jew, Baha’i, Jain, Shintoist, Caodaiist, Zoroastrian, Pagan or Rasta? Or should you perhaps choose one of the hundreds of other religions that currently exist or have existed in the past? It may seem obvious to some people that the bigger religions are far more likely to be the one true religion, but no religion represents more than 50% of the population today, so clearly whatever God or Gods are out there aren’t too concerned about making their message easy to discover. Furthermore, the popularity of religions has risen and fallen over the centuries and will surely continue to do so in the future, so why should we think that what is most popular today is somehow superior to what was popular in the past or what will be most popular in the future? At best, we can say that (on account of their size) larger religions might be slightly more likely to be true, but a strong correlation between truth and size does not seem likely, given the factors mentioned.

Most people accept the religion that they were taught as a child, but of course there is no reason to assume that the religion that you happen to be born into is more likely to be correct than any other. Rather than trying to guess which religion is true, we might try the approach of attempting to minimize the suffering we would incur by selecting the wrong religion. This would be done by trying to convince ourselves to believe in the religion that claims the worst punishment for non-believers. But given the very large number of fundamentally conflicting religions out there, whatever this most punishing religion happens to be it has a high probability of being a false one, and hence even if there does exist a true religion at all, you are probably not protecting yourself. After all, someone could start a new religion right now which has a punishment far worse than any other religion that has ever existed. Intuitively, we would imagine that this religion is very unlikely to be true, and yet by this selection method we would choose to believe in it to avoid that worst of all punishments.

Another thing to consider about pascal’s wager is that forcing yourself to believe in a religion simply to avoid hell or some other sort of punishment (or gain a promised reward) may well have negative consequences in your life today. If the religion turns out to be false then you will have a false understanding of reality, which may lead to bad decision making. You could spend a large amount of your time doing rituals to please a non-existent being, and might expend a lot of energy trying to convert others to this false religion. In the case of some religions, you may actually be required to give up part of your salary or time in service to it.

It seems that taking Pascal’s Wager has a low probability of protecting you unless the following conditions are met:

a) You somehow can be sure that only a small number of religions have a significant chance of being true, and can therefore eliminate the hundreds of other religions from consideration.

b) You are able to convince yourself to truly believe (and not just pretend to believe) in the religion of your choosing.

c) You manage to follow the rules of the chosen religion carefully enough to avoid the punishment for non-believers.

d) The particular sect of that religion that you choose has not distorted the true teachings too much.

e) You can be reasonably confident that the chance of SOME religion being true is quite high.

f) You don’t reduce your happiness so much while practicing the religion or miss out on so many earthly pleasures that all is wasted if it turns out there is no God, or the religion you chose was false, or the sect of the religion you chose had distorted teachings or you misinterpreted your religion’s teachings or you failed to obey the teachings closely enough to avoid punishment.

5. Since almost every human society in the past 4000 years has believed in and worshipped God (or Gods), isn’t that compelling evidence that God really exists, and that each of these groups has discovered some of this truth?

Unfortunately, the fact that most societies have worshipped a god of some kind does not provide compelling evidence for the existence of gods. To the contrary, it provides strong evidence that humans are very prone to making gods up and very adept at believing in these made up creations. The reason, simply put, is that the huge number of religions that humans have created contradict each other on such fundamental questions that there is no possible way that all of them or even the majority of them could be true at the same time. These religions disagree with each other about how many gods there are, what a person needs to do to please the gods, whether there is a soul, what happens to humans after they die, the codes of laws we all should follow, how the earth and the universe originated, and many other important question. Hence, the most reasonable interpretation of the the fact that religions are so ubiquitous is not that all of the religions are somehow tapping into some basic truth, but rather that they include a great deal of falsehood that was made up by (and fervently believed by) human beings. If even one major world religion is false, that would be enough to demonstrate our potential for deeply and unquestioningly believing falsehood en masse. Even under the assumption that at least one religion is true, there have likely been dozens (or more likely, hundreds) which contained little truth, and which effectively were all worshipping different gods.

6. Even if some spiritual and religious beliefs are not true, why does it make a difference, so long as these ideas bring joy and meaning into people’s lives?

While in general it is great when an idea improves someone’s life without negative consequences, false beliefs can have a variety of costs associated with them, and sometimes falsehoods lead to other falsehoods, entrenching a person deeper into delusion. Religion and spirituality (even when not founded in the truth) can definitely have some advantages for certain people. For example, false religion can at times:

a) Provide a sense of community.

…but there are many ways a person can find community.

b) Reduce one’s fear of death.

…but it is possible to reduce one’s fear of death without religious belief (such as by employing modern psychological methods like CBT, learning to view death as a release from the suffering of disease and old age, or considering whether immortality would really be better than death).

c) Give a person comfort when reflecting on loved ones they have lost.

…but comfort can also be found by reflecting on the good and the joy in the deceased persons life, and on the fine moments spent together.

d) Cause people to behave more altruistically out of fear of punishment or promise of reward.

…but many atheists behave altruistically without the threat of punishment or temptation of reward, and it seems that a certain degree of altruism is built into our genetic code.

e) Encourage a loving and sympathetic nature (“love thy neighbor as thyself”).

…but many people cultivate a loving attitude towards others without religion, and recognize that cultivating a love for others nature is very fulfilling in it’s own right.

f) Provide purpose in one’s life (e.g. following gods will, or getting into heaven).

…but many atheists feel like they have a genuine purpose in life, whether it is to help others, find happiness for themselves, or promote an idea that they think is of great importance.

g) Give a person the feeling that they are not alone and that they are being looked after.

…but many people feel that they are looked after by friends and loved ones or by the government, and so don’t need to imagine that their are spiritual beings doing this job.

h) Give a person the good feeling that their is justice in the universe (good behavior is rewarded, bad behavior punished).

…but a lack of supernatural justice can motivate us to try to create justice on this earth.

i) Give a person the comforting feeling that bad things happen for a reason.

…but bad things usually have a silver lining which can be seen if we look hard enough, even if that lining is only a lesson to be learned

j) Make a person feel like they understand why things are the way they are.

…but we can learn a lot about the way things truly are without needing to delude ourselves with false wisdom.

In other words, while false religion can provide benefits for some people, it is not essential for attaining these benefits. What’s more, false spiritual beliefs can unfortunately lead to many negative consequences as well. They can at times:

a) Create conflict between or prejudice among groups with different beliefs (e.g. hatred of jews, distrust of muslims, etc).

b) Create intense and terrible fear of supernatural punishment (e.g. of being burned alive for eternity in hell).

c) Fill a person with fear that loved ones will be punished after death.

d) Cause people to behave in destructive ways out of fear of punishment or promise of reward (e.g. suicide bombers, abortion center bombers, etc.)

e) Encourage a distrustful attitude towards non-believers and atheists and those who violate religious laws (e.g. homosexuals, according to some religions).

f) Provide a self destructive purpose in one’s life full of great but futile sacrifice, like devoting much of one’s time and money to reaching a non-existent heaven or converting others to one’s own false beliefs.

g) Give a person the disturbing feeling that the devil is out to get them or corrupt them (e.g. in 2007, 70% of Americans said that they believe in the devil).

h) Give a person the false expectation that whenever they good things, they will be rewarded for them, which could lead to disappointment or disillusionment if the reward does not come.

i) Make a person think that when tragedy befalls someone else, the person necessarily must have caused it in somehow by their thoughts or actions (an idea espoused in the popular book “The Secret”, among others).

j) Give a person the false impression that they understand why things are the way they are, which could lead to them making bad decisions based on their bad information.

What’s more, religion can lead to terrible feelings of guilt, especially over sexual matters (e.g. masturbation, sex, homosexual impulses, lust, etc.). It can also lead to unwanted pregnancy (through rules prohibiting contraception), religiously justified wars (e.g. the Crusades), cruelty towards outsiders (such as occurred during the witch hunts and the Inquisition), the use of ineffective quack medicine (e.g. prayer healing and faith healing which are promoted by many spiritual systems), and it can lead to false predictions about what will occur (e.g. If I pray that I find a better job it will increase my chances, if I act on my sexual urges God will punish me, and if I check my astrological chart it will tell me what decisions are good for me).

In conclusion, false religious belief has it’s advantages and disadvantages. It is often underestimated just how serious these disadvantages can be (to get an idea of the potential impact consider what some cults do to their members and keep in mind that false spiritual beliefs are what allows this to happen). Many or most of the advantages of spiritual belief can be achieved via other means which do not carry with them the dangers of false religion.

7. Since science tells us that ever effect has a cause, there must have been a first cause. Wouldn’t it be fair to call this first cause “God”?

The idea that “every effect has a cause” is an idea that we develop from our experience in the everyday world. It is certainly not a scientific theory (you won’t find it in any science textbooks, though you will find it in some theological ones), and sometimes our intuition about the way things work (such as the idea that time always runs at the same pace, or that particles have well defined positions) end up being painfully inaccurate when we start exploring regimes outside of our usual experience (such as huge scales, tiny scales, enormous velocities and huge energies).

As a matter of fact, it is difficult to even define rigorously what is meant by a “cause”. If a politician is assassinated by three snipers shooting him at the same time, assuming that he would have died had any of those snipers not been involved, which sniper was the cause of his death? All of them? None of them? The answer isn’t clear. Furthermore, suppose that there is an apple on an apple tree. Who caused the apple to be there? Was it the tree that caused it? Or was it the gardener who took care of the tree? Or was it the woman who decided to plant the tree? Or was it the botanist who developed that particular type of apple?

Even if we do manage to come up with a sensible and consistent definition for causation, it is still not clear that there must have been a first cause. For example, if the universe always existed then there could be an infinite chain of causes and effects with no beginning stretching back for eternity. What’s more, evidence now points to the idea that not only did the universe start at the moment of the big bang, but time may have started at that point as well. Without time, it is not clear what it would mean for something to exist “before the big bang”, and therefore it may not even make sense to say that something caused the big bang.

Another problem with this “first cause is God idea”, is that even if there was a first cause, it is unclear why we should call this God. Sure, we can use whatever word we like for it, but that doesn’t mean that it has any of the properties that are often ascribed to God (such as intelligence, omnipotence, love, etc.)

A final point to consider is that if God was the first cause, then we are implicitly assuming that nothing caused God. But why are we willing to accept the idea that a being like God could always exist without cause, yet at the same time assume that everything else needs a cause to exist? This seems like an assumption for which we have no evidence, and it seems to undermine the original proposal that every effect has a cause.

8. Without religion, what reason does anyone have to be ethical? Won’t everyone just behave in a selfish, hedonistic fashion?

Fortunately there are strong genetic and social component to ethics that exist independently of religion. The vast majority of non-religious people enjoy loving and mutually beneficial relationships, get pleasure from doing good things for those that they care about, and feel guilt when they hurt others without some kind of justification. Even religious people usually have some ethical principles that exist independently from their religions. For example, many Protestants feel that divorce is morally acceptable despite the fact that divorce is specifically condemned by Jesus. Furthermore, many Christians feel that masturbation is an immoral practice (even when fantasizing about one’s own spouse), even though it is not actually mentioned or condemned in the Bible. What’s more, many Americans (both christian and non-christian) are disgusted by the idea of marrying a 1st cousin, even in the case where the woman is infertile and hence their is no chance of genetic abnormalities arising, and even though the practice is common in the old testament and in other cultures today. The empirical evidence tells us that without religion, most people still have moral principles that they will choose to adhere to.

What reasons do religious people have to follow the rules of their religion? Either, they want to attain the reward their religion offers (e.g. heaven), they want to avoid their religion’s punishments (e.g. hell), they want to avoid social ostracization, they want to be thought of as a pious and good person, they want to feel like a good person, they enjoy following the religious rules, or they feel like they owe something to their God or gods and follow religious laws out of a sense of obligation. Likewise, what reasons do non-religious people have to follow societal (or their own personal) principles of ethics? Either they want to avoid punishment from the law, they want to avoid social ostracization, they want to be thought of as a good person, they want to feel like a good person, they enjoy following their ethical principles, or they feel a sense of duty to be ethical. Essentially, the motivations that the religious and non-religious have to be good are very similar.

9. Even a single celled organism is far too complex to have come into existence through chance alone. So if evolution is true, how could life possibly have started?

First of all, given enough time, enough space, the right kinds of atoms and appropriate levels of energy, any conglomeration of particles that is capable of occurring will occur. Hence, if the universe existed for long enough and is large enough, we SHOULD expect a single celled organism to pop into existence just by chance once in a very long while, since this event is not impossible, only very, very, very rare. That being said, evolutionary biologists do not claim that single celled organisms came into existence on earth by chance alone. Rather, evolution predicts that before life existed on earth, it is a simple, self replicating molecule that came into existence through chance collisions. This molecule replicated and spread through the waters that at that time covered our planet. Since the copying mechanism of this molecule was imperfect, every so often a copying error occurred. While most of these errors lead to molecules that copied less effectively than their parent, every so often they copied even faster or more efficiently. This scenario is believed to have been sufficient for the process of natural selection to get going, leading to ever more efficient molecules, and eventually conglomerations of molecules, all competing for copying resources. The first single celled organism would then be an ancestor of these very simple replicators. Evolution’s method for developing single celled organisms is vastly more efficient than waiting around for a single celled organism to pop into existence by chance!

10. If evolution is true, then why haven’t scientists been able to discover any “transitional forms” or “transitional fossils” that represent intermediates between species?

As a matter of fact, scientists have discovered many transitional fossils that bridge the gap between major categories of species. To give just a few of many known examples, Archaeopteryx is an animal that has many features of both dinosaurs and birds, Kutchicetus is thought to be a transitional form lying between land mammals and whales, and Tiktaalik is believed to link fish and tetrapods. More importantly though, the theory of evolution tells us that all creatures are “transitional forms” because species are constantly in flux, with each subsequent generation differing slightly from the last due to genes being combined in new ways and new genes forming via mutation. The categories that we create like “fish”, “reptile”, “amphibian”, “mammal”, etc. are simply useful labels, but we could have chosen to divide animals in many other ways, and in fact there are a great many creatures that have lived that do not fit neatly into any of these groups (since evolution works through gradual change).

An important fact to keep in mind is that fossil formation is extraordinarily rare (depending both on the local environment and on the composition of the species), and those fossils that do exist can be buried deep underground. Since extinction is fairly common, It therefore should not be surprising if we have never found fossils for (and therefore, probably don’t even have names for) most of the species that have ever existed.

Some people expect that if evolution were true there would have been creatures like crocoducks (a creature half way between a crocodile and duck). Of course, no such species ever existed, because ducks do not have crocodiles as ancestors. Crocodiles and ducks do have a common ancestor however, but it probably did not look much like either a crocodile or a duck, and given how common extinction is and the rarity with which fossils are created and found, we likely do not have fossil similar to this common ancestor. What’s more, even if crocoducks did exist (i.e. ducks were the ancestors of crocodiles), if we ever found one of their fossils this would simply lead people to claim further gaps in the fossil record since we would still not have fossils lying between crocoducks and ducks or between crocodiles and crocoducks. Hence, gaps in the fossil record are not only expected but impossible to avoid, but that says nothing about either the truth or falsehood of evolution.

Sadly, most of the attacks on evolution are made by people who either don’t understand the theory, or who do understand it but choose to misrepresent it to further a religious agenda. Anyone who (like Kirk Cameron) who mentions the crocoduck as a “problem” for evolution is seriously confused.

11. If God does not exist, and evolution is true, doesn’t that make life meaningless? If life is without meaning, what is the point of doing anything at all or even going on living?

If God not not exist and it is also the case that evolution is true, that does not mean that we cannot experience a great deal of meaning in our lives. It may however mean that there is no overarching “purpose” for life, other than as a necessary consequence of the natural process we call evolution. Most of us wouldn’t ask what the “purpose” of rainbows is, as our ancestors might have, because we know that they come about as a consequence of the physics of light and the refraction caused by moisture droplets. Likewise, the existence of life on earth is a necessary consequence of the natural process we call evolution and the fact that earth’s early state was amenable to the formation of self replicating molecules. This being said, our lives are indeed very meaningful to us, and we can choose to fill them with actions and emotions that give us a strong sense of purpose. Very few people live their lives merely because they think life itself has an over arching purpose. Filling our lives with joy, love, and other positive emotions provides plenty of motivation to go on living, and we are free to choose what we want the “point” of our own lives to be by seeking that which leads to our personal fulfillment.

12. If there isn’t something “more” to life than what science tells us, how can we explain mysteries like memories of past lives, mystical experiences, psychic connections, the feeling people have that God is with them, etc?

There are many things about the universe that scientists have not yet been able to explain. To give just a few of many examples: the Big Bang, human consciousness, how memories are stored, and how (in detail) the brain generates emotions. However, science does provide explanations for many experiences that are generally thought of as being spiritual or of a paranormal nature. To give some examples of how one might respond to various spiritual or supernatural claims from a scientific perspective:

- Hearing the voice of God speaking to you, or seeing an angel.

More than 10% of people will experience intense visual or auditory hallucinations at some point in their lives. These experiences can be brought about by many causes, including by schizophrenia, epilepsy, sleep deprivation, and sleep paralysis. We know for a fact that many experiences of a religious nature are hallucinations, so it is not such a great leap to assume that most or all of them are. Since we know that many people would say that they heard the voice of God and saw angels even if these beings don’t exist, the fact that people make such claims (which, of course, we have no way to independently validate) does not constitute scientific evidence for these beings.

- Remembering past lives.

Human memory is highly fallible, and it has been demonstrated that false memories can be created (or even implanted) that seem totally convincing. Is it not possible that people’s “memories” of past lives are in fact false memories? Many past life stories come from children, who are highly suggestible and also prone to using their imagination. What’s more, many people makeup extravagant stories merely to get attention. Finally, with more than 6.7 billion people on this planet, extraordinary coincidences are bound to happen quite often, so we cannot simply assume that because an event was very unlikely it was not caused by chance (we tend to hear about the rare, extremely unlikely and remarkable events, not the billions of likely and ordinary ones).

- Mystical experiences, such as ecstatic states, and feelings of nirvana or enlightenment.

The human brain is capable of generating all sorts of interesting and powerful emotional states, ranging from enormous anxiety to joyous ecstasy. While people’s descriptions of some mystical mental states may well be genuine attempts to describe the way in which they actually felt, there is no proof that these states represent anything other than specific chemical configurations of the brain. Feeling that we are “one with the universe” or “close to god” is not the same as actually being “one with the universe” or “close to god”. A number of “mystical” experiences have been induced by altering the operation of the brain, either through chemicals (like Psilocybin, the hallucinogen found in some mushrooms) or through magnetic stimulation of the brain (as is used in the God Helmet). Other bizarre internal experiences seem to be caused by epilepsy, migraines and even strokes. Hence we do not require the existence of Gods, spirits, or paranormal phenomena to explain these experiences that people have. Of course, even if these experiences can be explained simply by changes in the brain’s state, that does not imply that these are not deeply moving experiences that can sometimes have profound effects on people’s lives.

- Psychic powers and connections

There is not credible scientific evidence that psychic phenomenon really exist. Professional psychics are known to employ a variety of tricks also used by magicians for simulating psychic ability, such as distraction, cold reading and hot reading. When people claim to have ESP related experiences in their own lives, they often are making the mistake of believing that a highly unlikely event has an explanation other than coincidence. For example, if you move your hand to pick up the phone to call your friend and your friend is calling you at that same moment, does that reflect a psychic connection or just a very improbable event? The answer is that while it is very unlikely that such a thing happens to any given person, it is very highly likely that it will happen to at least one person in the world each and every day. The only way to study psychic phenomenon is in a very carefully controlled laboratory setting, and even then, the research must be replicated by multiple, independent researchers in order for it to be considered reliable.

In conclusion, we see that science does provide explanations for these experiences that so many people assume are outside the realm of science. While these explanations do not satisfy many people who very much want to believe in supernatural phenomena, they are sufficient to explain the phenomena in question using ideas that (unlike the supernatural) have been validated by science.

13. The are only three possibilities about Jesus: he was a liar, a lunatic, or the son of God. Since he does not seem either to be a liar or a lunatic, does that really mean that he must be the God’s son?

This is actually a false trichotomy, as there are other possibilities besides the three mentioned. For example, it could be the case that the Bible does not represent the exact words that Jesus spoke, and therefore that we don’t really know what Jesus said for sure. There is general consensus that there was at least a 7 year gap (and possibly much longer) between when Jesus died and when the first of the New Testament books was written down, with the other books following somewhere within the next decades. It is unlikely that the precise words that Jesus used would be perfectly preserved without any modification over this period. What’s more, we do not have any copies of the original New Testament, with our earliest fragments being dated more than 70 years after Jesus’ death. Finally, there are a variety of early versions of the New Testament, reflecting changes that had been made to the original text, and it is unclear which of these is to be considered authoritative. All of this evidence points to the idea that we do not know for sure what Jesus said, and it would be a miracle indeed if their were not many misrepresentations of his words in the Bible as we know it today. Some Christians might argue that God would not have allowed the true words of Jesus to have been altered, but that argument amounts to assuming the existence of the Christian God in order to prove the legitimacy of Jesus, which is a circular argument in this context.

Another possibility is that Jesus may not have existed at all, in which case he would be neither a liar, lunatic, nor the son of God. However, if we are willing to assume for a moment that Jesus did exist, and that the Bible does reflect his message very accurately, then it probably safe to assume that he was either lying, delusional, or in touch with God. Of course, it is also very possible that he was a mix of these things (e.g. delusional about some things while lying about others, while still more details could have been invented by his followers or by scribes). Without assuming at the outset that Jesus was the son of God, it is very hard to prove that he was never lying and never delusional.

14. Is science just a form of religion? Don’t scientists take many things on faith?

To prove that science is not a religion, it is sufficient simply to check the definition of religion. According to the Merriam-Webster dictionary, the primary definition of “religion” is “the service and worship of God or the supernatural”, or “commitment or devotion to religious faith or observance.” Since science is only concerned with natural things, it clearly does not fit the first definition. Furthermore, the scientific method is based on gathering evidence, and testing beliefs based on experiment, which is precisely the opposite of faith (which is belief held in spite of a lack of evidence). Of course, since scientists are only human beings, they believe many things in their lives that are not based on rationality and evidence, and sometimes hold beliefs that require faith. Furthermore, evidence is occasionally faulty and scientists sometimes arrive at the wrong conclusions based on legitimate evidence. However, the scientific establishment more than any other human establishment is designed to reject personal opinion and accept only that which is confirmed by independently verifiable experiments. While scientists cannot confirm every piece of evidence for themselves, and therefore must trust other experts for information, this is always the case in every endeavor (since no one has the time to check every single fact), and it is probably fair to say that believing in scientific results requires less faith than believing in the results of any other academic field.

The Formation of Life

The theory of evolution tells us that given the right conditions (a sufficiently powerful source of energy, the right kinds of atoms, etc.) life can form through a natural and essentially automatic process. Scientists do not understand the precise details of how this occurred on our planet (which shouldn’t come as a surprise, given that the event happened billions of years ago on a microscopic scale during a time when earth had a very different chemical composition then it does today) but they do have reasonable conjectures. What seems very likely is that prior to life there existed what we might call pre-life: simple, self-replicating molecules, the first of which was formed by a lucky collision of atoms. These replicators would occasionally make errors while copying themselves, which most of the time would be disastrous to the reproductive capabilities of their offspring (destroying the possibility of further replication), but which every so often would lead to slightly more efficient replicators. Of course, copying requires the use of chemical materials, so the replicators would be in competition with each other for molecular resources. Over time, through the processes of natural selection, those replicators that were most efficient at surviving and copying themselves in the prevailing environment would spread wider and faster than the others. Over many generations, the lineages of replicators that survived would get progressively better suited for their environment, very slowly becoming what we would recognize as life.

If this process of life generation can spontaneously begin on earth, then it can occur on any other planet, assuming that the planet has sufficiently favorable conditions for a sufficiently long period of time. In particular, since the laws of physics on earth appear to be precisely the same as those that govern the rest of the universe, and since the universe looks to be approximately the same in every direction, we should anticipate seeing other earth-like bodies distributed throughout the universe (in terms of size, position within their solar systems, chemical composition, etc), and we should expect that these planets have a probability of developing life that is similar to the chance earth had. It may be possible that life could take forms that are difficult for us even to imagine, occurring on astronomical bodies that are not very much like earth at all, but since life occurred once on a earth-like planet, earth-like planets are our best guess for where we can expect to find alien life.

It is estimated that there are far more than a trillion planets†† in the universe, providing a staggering number of opportunities for life to begin. Furthermore, the universe is more than 13 billion years old†, so there has been an enormous amount of time for life creating processes to take place. Given enough planets, it is inevitable that at least one will be sufficiently like our early earth to house life. Given enough time, it is inevitable that life will eventually form on such a planet. Hence, the spontaneous formation of life on earth indicates that life very likely exists elsewhere in the universe, though estimating the actual probabilities involved is tricky. The question of exactly how much life has existed in our universe can be reduced to a question that can be studied empirically through scientific means. Essentially, one needs to calculate how many planets (or other astronomical bodies) in our universe today are likely to have undergone long periods during which conditions were suitable for life to begin. Unfortunately however, even with the best telescopes our ability to peer through the vast expanses of space is severely limited, and our understanding of planet formation and evolution is far from complete, so this question is unlikely to be adequately answered for a long time. Ultimately though, the question of the existence of aliens is a scientific one, and therefore we should expect scientists rather than philosophers to eventually have the greatest insight into its answer.

Traveling Through the Universe

Some people believe that intelligent life is unlikely to exist outside of our planet, because if it did, we likely would have encountered it by now. This belief reflects an ignorance of the incredible size and spaciousness of the universe. To give an illuminating example, suppose that humans were interested in traveling to the star (other than the sun) that is the closest to our earth. This star is Proxima Centauri (a red dwarf, it turns out), at a distance of about 4.2 light years from earth. That means that if a space shuttle traveled to Proxima and back at the speed of light, 8.4 years would have elapsed on earth by the time they returned. In practice though, the equations of Einstein’s theory of relativity tell us that it would take an infinite amount of energy to get a massive object to move at light speed. We therefore might employ the more realistic assumption that the space shuttle traveled at about 25% of the speed of light (or, as a physicist would say, 0.25 C). This would still be an incredible scientific achievement, considering that it is about 37,000 times the speed of the fastest plane. To get a space shuttle (weighing, say, 24,000 kg like some space shuttles do today) going at this speed would require a minimum (assuming perfect efficiency in converting potential energy to kinetic energy) of about 67 million terra joules (actually, slightly more, taking into account relativistic effects), which is approximately 280 times the energy released by the most powerful nuclear weapon ever created. Of course, naively setting off 280 nuclear weapons of this kind would be far more likely to kill all life on earth than to get an object close to the size of a space shuttle traveling at the desired speed. As a matter of fact, the process would have to progress rather slowly. Since the human body is limited in the amount of acceleration it can withstand (before blood pools heavily in the legs, and worse), it would take a minimum of 15 days of accelerating to get up to this enormous velocity (unless drastic means were taken, such as keeping the astronauts submerged in fluid during acceleration). In the end, even with the stupendous speed of 25% of the speed of light, a journey to Proxima and back would take over 33 years from the point of view of someone on earth, more than a third of a human life span, and long enough to ruin all of one’s personal relationships. And let us not forget, all this would get us is a roundtrip voyage to our second closest star! The universe is an extremely spacious place, and even for an alien civilization far more advanced than ours, it would take an enormous amount of time to explore even a single galaxy, let alone the more than a hundred billion galaxies that are thought to exist. Our own milky way galaxy is thought to contain approximately one hundred billion stars, and from the point of view of someone on earth, a traveler moving at the speed of light would take approximately 26,000 years to reach earth from our galaxy’s center. In particular, this means that aliens located at our galaxy’s center could not possibly be aware of the first human radio broadcasts for many thousands of more years. Finding alien civilizations, and exploring a galaxy is long, hard work!

There is an important point to be made about the way in which Einstein’s theory of relativity relates to travel at speeds approaching that of light. Because of an effect known as time dilation, time literally moves slower for a traveler that accelerates than it does for the people (or should I say creatures?) on the traveler’s home planet. At speeds like 25% the speed of light, the effect is a rather minor one, but at 99% the speed of light or faster it is very pronounced. In a sense, this provides a space travel loophole, because an alien could theoretically travel extremely long distances at close to the speed of light without aging very much (though, the rest of the universe would continue to age normally of course, so their loved ones would probably die off before they returned from their journey). For example, while a trip from our galactic center to earth would take about 26,000 years for a traveler moving at the speed of light from the point of view of someone still on earth, from the point of view of the traveler himself the journey would feel almost instantaneous. The trouble with using this method for space travel, however, is that the closer to the speed of light one wants to travel, the more energy is required to do so (with, as we have said, an infinite amount of energy being needed to travel at light speed exactly). Hence, time dilation comes at the price of dramatically increased energy requirements. It is also probably worth mentioning that a ship traveling at these sort of speeds would be insanely difficult to navigate. There would be very little time to change course to avoid any interstellar objects, and at the speed of even only 25% the speed of light, a rather small piece of rock or ice carries an enormously destructive amount of momentum. All this being sent, with phenomenal technology, an enormously plentiful energy source, lots of time for acceleration, incredibly good navigation systems, no desire ever to return home again, and a lot of luck, aliens might be able to get from planet to planet quickly without aging very much in the process. The amount of aging they would undergo on such journeys depends on how close to the speed of light they can get without destroying themselves or using up their energy source. A hypothetical method that has been proposed for achieving speeds close to that of light is the Bussard ramjet, which involves using powerful electromagnetic fields to harvest free floating space particles during flight, and converting them to energy with a fusion powered rocket.

What about traveling at speeds beyond that of light? Unfortunately, as far as physicists can tell, no object can ever go faster than light. Of course, we can never rule out the possibility that science not yet discovered will one day allow that possibility, but the extremely well validated theory of relativity currently denies it. That being said, there are at least a couple of ways that the light speed constraint can theoretically be circumvented without actually breaking the ultimate speed limit, but they may not be of any practical use.

Quantum theory predicts the existence of “wormholes”, which are essentially open passages that connect two points in spacetime. While wormholes have as of yet never been observed directly, they may exist at an extremely small scale, popping into existence for miniscule amounts of time and bridging together very short spacetime distances. Expanding or creating large wormholes, getting them to stabilize for reasonably long periods, and controlling which parts of spacetime they connect are currently very far beyond the scope of modern science. It could easily turn out that worm holes are essentially useless from a space traveler’s perspective, no matter how advanced technology has become. Some initial calculations done by physicists of what it would take to create a useful wormhole make demands that are probably beyond the scope of ANY civilization. Some physicists have argued that large, stable wormholes could already exist strewn throughout the universe, a consequence of the inflation of the universe after the big bang. While wormholes like these could potentially be useful for interstellar travel, locating them and actually getting to them could itself be extremely difficult, and since their pathways would already be determined they would not provide much flexibility to a traveler. It is worth mentioned that these strange tunnels can cut through time as well as through space, transporting a traveler into the past while at the same time altering his position (though a wormhole could not take you back to a time prior to when it was created).

Another, totally different way that the speed constraint of relativity is sometimes circumvented is through the phenomenon known as quantum tunneling, where tiny particles jump locations approximately instantaneously. Unfortunately though, this is inherently an unpredictable process, and therefore not useful for controlled traveling. What’s more, like worm holes, this phenomenon is only known to happen at miniature scales, far smaller than even a single celled organism. In the macroscopic world of massive objects like people and spaceships, quantum tunneling is never observed.

As we have said, if aliens managed to achieve speeds nearing that of light, they would be able to explore the planets of their galaxy without aging a great deal. However, from the point of view of planet earth the process would still be extremely slow (the aliens would experience time dilation due to their enormous acceleration, causing time to run more slowly for them than usual, but we would age at our normal pace). If, for example, there were aliens at the center of our galaxy traveling at almost the speed of light directly towards earth, they might find earth in what to them is a few years, but what for us is more than 500 generations. Hence, even if aliens knew where we were located, had a desire to get to us, and didn’t care about ever returning home (after all, their own civilization might be extinct by the time they returned) we would be waiting an enormous amount of time before they got here. By the time they arrived so much time would elapsed that our planet might be destroyed, or our technology might have become as good as their own (making us a potential threat). Unless an alien civilization was lucky (or unlucky) enough to have evolved on a planet very nearby us (by which I mean, within a few dozen light years), even discovering where we are located would be highly problematic. While it is true that the radio waves that we transmit travel at the speed of light, and might potentially be detected by another civilization, these signals grow dramatically weaker as they propagate away from earth, and by the time they are a hundred light years out may be extremely hard to detect (especially when mingled with many natural interstellar sources of noise).

It is probably worth mentioning that there are some reasons to think that aliens might not travel all that much around their galaxies even after they are able achieve speeds near that of light. For one thing, humans already have the technology to destroy all life on earth, and we aren’t yet anywhere close to having ships that can quickly carry humans through interstellar space. It may well be the case that most alien civilizations that exist destroy themselves long before gaining these capabilities. If, as seems to be the case, creating massively devastating weapons is much easier than near light speed travel, civilizations might generally not last long enough to travel. On the other hand, if near light speed travel is sufficiently difficult to achieve (requiring, say hundreds of thousands of years of research by modern humans), then species might tend to be destroyed by natural disasters (such as supernova) before acquiring the technology. What is more, it is interesting to consider the role that virtual reality would likely play in an extremely technologically advanced civilization. If essentially any experience can be had virtually, the need felt to travel outside of one’s own planet (let alone, to ever leave the virtually constructed world) may become limited. Once a civilization comes to construct and accept a virtual world that accurately simulates experiences, but in which one can create or do whatever one one wishes (perhaps even invoke pleasurable feelings upon command), how much time would creatures really choose to spend in the real world?

Aliens Here On Earth?

What is a person to make of the innumerable tales of alien abductions, alien autopsies, crop circles, and spaceship sightings that have been floating around since the 1940’s? While it is impossible to examine every single one of these cases (there are far too many), upon close examination every case that I know of that was thoroughly investigated did not provide solid evidence for alien life on earth. Most of the alien abduction stories come with no corroborating evidence whatsoever (only witness testimony), and most of them occur just after (or during) sleep. Hence, it is impossible to rule out the very mundane explanations of lucid dreaming, sleep paralysis, deliberate fraud, misperception, drug use, illness, and psychosis as explanations for these alleged experiences. Once the idea of aliens became popularized back in the 1950’s alien creatures began to appear in great numbers in people’s dreams and hallucinations. As far as crop circles go, those have essentially been debunked as the work of mischievous (and creative) humans. A number of UFO sightings have turned out to be either unusual aircraft (such as air balloons), normal aircraft flying in formation, normal aircraft with unusual lighting, meteorological events, or tricks of the nighttime sky coupled with human perception errors. While many UFO sightings have gone unexplained, a lack of explanation is a far cry from proving that aliens are here on earth as there are dozens of possible explanations for a person claiming to see moving lights in the sky. In order to prove a point, professional skeptic James Randi once claimed on a radio show to have just seen a UFO. People began calling into the show, claiming also to have seen the same UFO that evenining, unaware that he had made the sighting up. Unfortunately, even photos of UFO’s do not provide good evidence as they can easily be forged (in fact, many of them are known to have been), or are ambiguous as to their interpretation. As far as alien autopsy videos go, those I have seen are obvious or known fakes (like the alleged Roswell autopsy video). Essentially, there doesn’t seem to be any strong evidence behind the alien sighting phenomenon, and it is clear that there is an enormous amount of human psychology involved. Even if aliens are on earth, the vast majority of alleged alien sightings are undoubtedly not genuine. Until actual alien technology is found (that has a function or material composition unachievable with human technology), an alien is actually detained, or video of aliens is taken that could not have been forged using computer generated imaging, it is wise to remain skeptical of stories about aliens.

An important point to keep in mind is that the fastest way that aliens have to discover that intelligent life exists on earth is to detect the radio or microwave signals that we produce. However, if the alien’s home planet is hundreds of light years away then our earliest signals would not even have reached them by now! In particular, since the invention of radio is less than 150 years old, the only possible civilizations that could have discovered that there is intelligent life on earth must be within 150 light years of us. Even worse, if aliens travel at a maximum speed of 25% of the speed of light, the only way that they could have both detected our signals and traveled to earth is if they were within 30 light years of earth when we first started broadcasting, which is a very tiny sphere compared to the size of our galaxy.

Contacting Aliens

While it is very unlikely that aliens have arrived here already, if humans continue to exist for another one hundred thousand years (admittedly a somewhat dubious prospect), it would not be terribly surprising if contact with aliens occurred at some point, most likely through electromagnetic signals rather than through direct face to face contact. Astronomers have now broadcasted messages into space, designed specifically to be detected and interpreted by technologically advanced aliens. Because of their design, these signals are more likely to be detected and properly interpreted than ordinary radio or television broadcasts. Unfortunately, contact with aliens may well be a very bad idea from the point of view of human survival. While aliens could potentially be friendly, there is reason to expect the opposite. Evolution, wherever it occurs, is a highly competitive process, requiring creatures to kill each other for resources. As essentially all creatures on earth (including humans) have many selfish and exploitative tendencies, it seems likely that aliens will as well. Under natural circumstances, creature that are too altruistic tend to be taken advantage of by more selfish individuals, and hence weeded out of the gene pool.

If humans are detected by an alien civilization in the next hundred years, the aliens will almost certainly have far superior technology to our own (by the very fact that they are able to detect us at all), and therefore could likely annihilate us with ease if they felt we might one day be a threat. With sufficiently powerful technology, for example, they could launch a weapon at us at near light speed. By the time we could even detect such an object (if indeed we would be able to detect it at all), there would be little time for us to understand it or react to prevent our destruction. The sad truth is that much of the time when groups of humans have encountered those who are much less technologically advanced than themselves (but who, nonetheless, are in control of useful resources), the weaker group has been suppressed, enslaved, or annihilated. Just look, for example, at the colonization of North America and Africa by Europeans. Unfortunately, it is not terribly unlikely that aliens would be similar to us in this regard. Even if there were only a 30% that the aliens would decide to kill us all, would that really be worth the risk? One thing to keep in mind is that if aliens do ever receive our signals and choose to respond to them in kind, the wise thing for them to do would be to obscure the origin of their messages, perhaps by reflecting them off of astronomical objects (to avoid the danger that we one day develop technologically strong enough to harm them). Hence, it is unlikely that contact with advanced aliens will actually allow us to identify their location.

Conclusion

While technologically advanced alien life is quite likely to exist elsewhere in the universe, it seems that it would be very difficult for these creatures to travel to earth, and perhaps even detect our existence in the first place. Moreover, if they did try to travel to us, it would almost certainly take an extremely long time (from our point of view) for them to make the journey. Finally, if aliens do visit us, there are reasons to think that the visit may be hostile. Unfortunately (or, perhaps quite fortunately) our only interactions with aliens in the next hundred years will almost certainly be only in our imaginations.

Suppose, for the sake of argument, that we somehow decide which stocks to include and which to exclude in our definition of the market (we might call this our “universe” of stocks). Matters get further complicated when we try to figure out the performance of our market over a given time period (for example, if we want to answer the question of whether the market was “up” or “down” in the past week). Should the market’s percentage return be defined as the average percentage return of all of our chosen chosen stocks? Or could we use the median return of these stocks instead? Or perhaps we should take a weighted average of each of the stock returns, where the amount that each of these returns counts is proportional to the market capitalization (a.k.a. market cap, which is the number of shares outstanding times the share price) of each stock (as in the Russell 1000 index). On the other hand, rather than weighting by market cap, maybe we should weight each stocks return by its float, which adjusts the market cap to include only those shares that are publicly available for trading (as in the S&P 500 index). One might even suggest that we weight the returns of each stock by the stock’s price (as in the Dow Jones Industrial Average).

How is one to decide between all of these different selection and weighting alternatives? Some popular choices to use as our definition for the U.S. market are:

1. The Dow Jones Industrial Average (a.k.a. The Dow) : The Dow is an infrequently updated group of thirty stocks from U.S. exchanges (but never utility or transportation companies) that are selected by the editors of the Wall Street Journal. The returns of these stocks are weighted proportionally to each stock’s share price. The Dow is probably the most frequently quoted stock market index in the world today, as well as the oldest market indicator (started in 1896). Unfortunately, it is also one of the worst market indexes in existence, in part due to the technological limitations at the time of its creation. Although highly correlated with other indices like the S&P 500, the fact that the Dow consists of only 30 stocks means that at times it can deviate substantially from broader market indices due to the volatility of individual stocks. What’s more, the constituents of the Dow are not generally representative of the industry breakdown of the stock market as a whole or of the United States economy. Finally, its method of weighting stock returns by share price is nonsensical: the share price is essentially meaningless, heavily influenced as it is by irrelevant factors such as the number of stock splits a company has had and the price at which shares were initially offered. It is time for America to abandon this subpar market index. The only really legitimate use that the Dow has is for looking at stock market characteristics over very long time periods (owning to its very early creation date). Unfortunately, as things stand today, when U.S. investors say “the market” they are typically referring either to the Dow or the S&P 500.

2. The S&P 500 : A float (formerly market cap) weighted index of five hundred of the largest market cap stocks that trade on the NYSE and NASDAQ exchanges. These stocks are chosen by a committee at Standard and Poor’s with the goal that they are representative of the industry breakdown of the broader stock market, and also that each of the stocks has sufficient liquidity, “financial viability”, and other characteristics. This index is probably the second most often quoted after the Dow Jones, and dates back to 1957. The S&P makes a lot more sense than the Dow, given its float weighting (which, roughly speaking, counts the returns of each stock based on how much the stock’s tradable shares are worth as a fraction of the value of all tradable shares of stocks in the index). This makes much more sense than the Dow’s price weighting, and can be interpreted as trying to approximate the average performance of a randomly placed dollar placed in the market. What’s more, the S&P 500 consists of five hundred rather than thirty stocks, which makes it better able to capture broad market changes and less susceptible to individual stock volatility. Unfortunately, its choice of which five hundred stocks to include is somewhat arbitrary from the point of view of most investors. In terms of total market capitalization, the S&P 500 represents “approximately 75% of the U.S. equities market.”

3. The Wilshire 5000 : A market cap (or in one version, float) weighted index of all companies with U.S. based headquarters that trade actively on a U.S. exchange and have “readily available price data”. This index has some advantages over the S&P 500, in that it is much broader (containing well over five thousand stocks), including a great number of smaller companies that the S&P ignores, and therefore may work better as an indicator of the entire market. It should be noted, however, that since the Wilshire 5000 is market cap weighted, the largest stocks count far more than the smallest ones, and so as it turns out the movement of the S&P 500 and Wilshire 5000 are pretty similar in practice, both dominated by their largest constituents. That being said, sometimes the performance of small market cap companies can diverge substantially from large cap companies, which alone can lead to performance differences between the two indices. One draw back of the Wilshire 5000 is that highly illiquid stocks that have very large erratic (and sometimes practically meaningless) movements in their stock prices can add volatility to the index. Another problem that the Wilshire 5000 suffers is that it contains so many different stocks that it can be difficult to replicate its actually return. Buying the appropriate number of shares of each of its constituents is difficult, both because of the large number of stocks involved, and because of the potentially low trading volumes that these stocks may have. This can be be a substantial draw back, as there are many investors who are interested in being able to achieve the “market” return (or, at least, a very close approximation thereof).

4. The Russell 3000 and Russell 1000 : These market cap weighted market indices contain the three-thousand or one-thousand stocks (respectively) with largest market caps that have headquarters in the U.S.

5. The Russell 2000 and S&P 600: These market cap weighted indices are designed to track the results of the smaller companies in the market (and are generally known as small cap indices). The Russell 2000 consists of the two-thousand smallest stocks from the Russell 3000, and represents approximately 8% of the Russell 3000’s total market capitalization. The S&P 600 consists of six hundred stocks that are selected in a manner similar to that of the S&P 500, but which are limited to have market caps between $200 million and $1 billion, covering approximately 3% of the total market cap of U.S. equities markets. For some investors, the Russell 2000 or S&P 600 may be more reasonable benchmarks to compare their performance against than large cap indices like the S&P 500. Since the S&P 500 is market cap weighted, and the largest market cap stocks are so very much larger than the average stock, the S&P 500 has a tendency to have its movements be dominated by a small number of extremely large companies. For investors that tend to buy smaller companies, the performance of the S&P 500 simply may not be that relevant to them. In practice, small cap and large cap indices can diverge quite substantially in their performance, especially over periods on the order of a few months. It is worth noting that since most stocks in the market are not as large as those in the S&P 500, the small cap indices may do a better job of capturing the behavior of more “average” stocks. On the other hand though, since people tend to think of the large cap indices like the S&P 500 as being “the market”, the large cap indices may do a better job of capturing market sentiment than small cap indices.

6. S&P Equal Weight Index : This index is constructed just like the S&P 500, but instead of weighting stock returns by market cap, the returns of all the constituent stocks are simply averaged together. This leads to a different sector allocation than the S&P 500, and performance that can differ fairly substantially. This benchmark may be appropriate for, say, investors who are limited to invest in only stocks with a large amount of liquidity, but who (once this constraint is satisfied) are not more likely to prefer larger stocks over smaller ones. Equal weight indices effectively capture the average performance that would be achieved if stocks were picks at random from the chosen stock universe.

As you can see, there are a large number of different indices that are commonly used, each of which has at least some claim for being called “the market” (at least, from the point of different individual investors). Ultimately, the best choice of which index to use depends on one’s goals. In many cases market indices are used to benchmark an investor’s performance, essentially determining whether she has performed better than her competition or asset class. In that case, the choice of which stocks to include in your definition of the market should effectively represent the universe of assets from which the investor has decided (in advance) to select their investments. For example, if upon founding their business, an investor has determined to only buy large market cap companies from South East Asia, then the market for that investor should consist only of stocks that meet those specific criteria.

As far as how stock returns should be weighted when constructing an index for benchmarking an investor, the two most natural choices are market cap weighting and equal weighting. Market cap weighting produces an approximate measurement of the average performance of each dollar that is allocated to a universe of stocks, whereas equal weighting produces a measurement of the average performance of each of the stocks themselves. If we want to answer the question of whether an investor’s capital outperformed the average return of a random dollar allocated to her universe of stocks then market cap weighting is the natural choice, whereas if we want to see whether an investor’s performance beat how one would do if they selected stocks randomly then equal weighting makes sense. Unfortunately, since smaller market cap companies tend to have larger, more random and more erratic swings in price, equal weighting stocks (especially fairly illiquid ones) can lead to very volatile (and sometimes essentially meaningless) market indices. The S&P Equal Weight Index avoids these problems to a large degree by limiting its universe to only very large companies, which tend to be very liquid and hence less prone to large, sudden fluctuations in stock price.

It is worth noting that while market cap weighting does have a certain intuitive appeal, it does not, by any means, do a perfect job of measuring the average performance of each dollar in a market place. One major problem is that market cap is not a fully satisfying measure of how much money is currently invested in a given stock. The problem arises because the price that we can sell one share of a stock for today (which is the price used in the computation of market cap) is not necessarily the price per share at which we could sell as many shares as we own (in fact, if we own a large block of shares we will often have to move the price slightly below the current market price in order to get those shares sold). This being said, if there is a better way than market cap weighting to measure the average dollar performance in a universe of stocks, I am not familiar with it.

Beyond benchmarking purposes, people frequently use measures of market performance as economic indicators, essentially treating the stock market as a proxy for business as a whole, or as a measure of the average performance of a dollar invested in the stock market. In these cases, it is generally desirable to use indices like the Wilshire 5000 because it consists of a very large number of companies and is market cap weighted. Since smaller companies do account for a significant portion of both business activity and stock market investment in the U.S., narrower indices like the S&P 500 may not be adequate for these economic indicator purposes.

In conclusion, while there are many possible ways that we may define the market, some of which are quite similar to each other in construction or performance, we should attempt to find the best possible definition to suit the particular task at hand. Ultimately, with so many options available, there is no reason to settle for a market index that is only “good enough”, since better decisions can be made using an index that is “just right”.