On Total Certainty About God

Posted on July 27, 2010 by clockbackward

IN a recent discussion about whether religions contain truth, my friend responded to one of my remarks with the common rejoinder “we cannot be 100% certain that there isn’t a God.” Indeed, she is correct, but the remark carries no weight. It is also the case that I can’t be 100% sure that I am not hallucinating right now, or that I am not in a dream, or that I am not a brain in a vat with nothing but computer simulated experiences. Total certainty is not a reasonable standard for belief, for there is nothing that a person can know that admits no possibility of error (except, perhaps, the truth of his or her own existence). What we perceive as absolute truth or irrefutable evidence could always be the result of a brain malfunction. Hence, if you require 100% certainty to have “belief”, then you will be left “believing” in nothing, rendering the word effectively useless. A much more reasonable usage would be one which allows for statements such as, “the odds are strongly in favor of X, therefore I believe in X.”

When it comes to belief about God, people often apply a different standard of evidence than they do to all other situations. Most everyone would be willing to say that “there is no rabbit living on the moon”, even though they cannot know this with certainty. After all, it is hypothetically possible that putting a rabbit on the moon was a part of some secret military project. And yet (despite their willingness to deny the moon rabbit), a great many people who find the existence of a God very improbable are not willing to say “there is no God” or even “I don’t believe in God.” This is likely, in part, due to cultural sensitivity (a claim that God does not exist certainly is offensive to some people) and it could also be related to the high stakes involved (if God is as he is perceived by many of the world religions, He has the power to punish and reward, so maybe it’s best not to bad mouth Him even if you strongly doubt His existence). But it seems that another factor at play is the bizarre and essentially ridiculous redefining of the word “believe” that occurs in the God context.

While I have met a great many non-believers and self proclaimed atheists, I have never heard anyone claim that they could absolutely disprove the existence of all possible forms of God. In fact, using some definitions of “God” (such as an unspecified “higher power”) God cannot be disproven even in theory. What’s more, I have again and again encountered people who, when asked whether they believe in God, claim they are agnostic, but when asked how probable they think God is, say something to the effect of “highly improbable.” If it is reasonable to say that “rabbits on the moon do not exist” when such rabbits seem highly improbable, why shouldn’t a person say “God does not exist” if they feel God is equally improbable? The (now somewhat popular) notion that those who say they do not believe in God think they can disprove Him with 100% certainty is not compatible with common English usage or with common sense.

Posted in God, Religion, Skepticism, Truth | Leave a comment

How to REALLY Answer a Question: Designing a Study from Scratch

Posted on July 16, 2010 by clockbackward

SUPPOSE that you are interested in answering a simple question: how effective is aspirin at relieving headaches? If you want to have conviction in the answer, you’ll need to think surprisingly carefully about your methods. Your first idea might simply be to take aspirin the next time you get a headache, and see if the headache goes away. But upon reflection, there are some problems with this.

First of all, since all headaches go away eventually, whether yours goes away or not isn’t really the relevant question. It would be better to ask how quickly the headache goes away. But even this question is not necessarily good enough, because even if aspirin doesn’t relieve a headache fully, a significant reduction in severity is still worthwhile.

In light of this, you may decide that when you next notice having a headache, you’ll make a record of how you feel every half hour for the next two hours. You’ll write things like “dull, throbbing pain of low intensity” or “sharp, searing pain over one eye”.

Unfortunately, just examining how you feel after taking aspirin a single time probably won’t be adequate, since the aspirin may be more helpful some times and less helpful other times. For example, perhaps it works on moderate headaches but not on really severe ones, so if your next headache happened to be really severe, it would look like aspirin was useless. To solve this problem and give yourself more data, you might resolve to make these records of how you’re feeling for each of the next 15 headaches you get.

There is still a problem though, because these subjective descriptions of headaches are difficult to compare to each other. It you take aspirin and your headache goes from a sharp pain over one eye to an intense ache over the entire head, have you made things better or worse? It would be difficult to aggregate the information from these varied descriptions over twenty different headaches to make a final assessment of how well aspirin is working.

Analysis would be a lot easier if you scored how unpleasant each headache was on a simple scale from 1 to 5 (1 meaning slight unpleasantness, 3, moderate unpleasantness, and 5, extreme unpleasantness). That way, you can simply look at all the scores you got just before taking aspirin and average them together. You can then compare this to the average of the scores 30 minutes after taking the aspirin and 60 minutes after taking it. That way, you can see if the amount of headache unpleasantness you feel really does drop substantially after taking aspirin.

You are interested in determining how effective aspirin is at relieving headaches, but all you’ve done so far is measure how good it is at relieving your own headaches. Perhaps you are more or less sensitive to aspirin than other people, or perhaps your headaches are more severe and harder to treat than most other people’s. To solve this problem, you enlist 20 people you know who are frequent headache sufferers. You get them to agree that, over the next 6 months, any time they begin to notice that they have a headache they will record how they feel on your 1 to 5 unpleasantness scale. They will then take aspirin and record how they feel again 30, 60, 90 and 120 minutes later.

But what if people take different doses? You might think that the aspirin isn’t working for some of them, but it’s only because they haven’t taken enough. To fix this problem, you hand them each an identical bottle of pills and tell them to take two whenever they get a headache (the maximum recommended dose). This also has the added benefit that everyone will be taking the same exact brand. That way if you find out that the aspirin really does work, other people can try to replicate your results by using the same brand that you did. On second thought, you also provide everyone with a timer that measures 30 minute intervals, to help them be more accurate about making records of their pain at almost exactly 30 , 60, 90 and 120 minutes.

There is still a problem though. You know that headaches often become less severe within an hour or so even when you don’t take aspirin. That means that even if someone’s pain score tends to have fallen 60 minutes after taking the aspirin, you don’t really know whether it is the aspirin that caused the reduction in pain or if the reduction would have occurred regardless. To remedy this, you come up with the idea of having only half of the people take aspirin when they have a headache, though everyone will still keep a record of their headache’s progression. Then, to see how well the aspirin worked, you can compare the average 30 minute and 60 minute scores of the 10 people who took the aspirin each time with the scores of the 10 people who didn’t take any aspirin. If the aspirin group’s pain fell a lot more than the non-aspirin group, then the aspirin probably was the cause.

But is it possible that the pain levels people record could be influenced by the act of taking a pill, independent of the chemical effect of the active ingredients? For example, what if, because they expect the aspirin to work, the people in the group taking the pills are more aware of signs of improvement? In that case, the aspirin would seem to work better than it really does. Or perhaps people’s expectations of improving could even influence how much pain they experience. Fortunately, these problems are easily remedied. Instead of giving half the group no aspirin, you instead give them pills in an aspirin bottle that look just like aspirin, but which have no effect on headaches. Sugar pills are a reasonable choice, because pretty much everyone has sugar in their diet anyway, and small amounts of it (like the amount in two little pills) won’t have any noticeable effect on a person.

This raises ethical considerations, however. You got people to agree to take aspirin, not to taking sugar pills. That means that beforehand you’ll need to inform everyone that they might be getting aspirin, but they also might be getting sugar pills instead. You can’t let them know which they are getting during the six months that they are recording their results, but afterwards, you can let them know which they were on. You’ll also have to get them to agree to not take any other headache medication during the experiment, and to record any medication that they do happen to take, or else it might throw off the results.

So half of your group will be taking aspirin, and the other half will get sugar pills. But who should get which? If, for example, the 10 people getting the aspirin have headaches that naturally (without treatment) last much longer than those of the 10 people that aren’t getting anything, then the aspirin may seem less effective than it really is.  Hence, you don’t want there to be any substantial difference between the two groups. A simple way to help ensure this is to assign individuals to the two groups (i.e. the aspirin group or the sugar pill group) at random. It is even better if someone else does the randomization (secretly recording which person is assigned to which type of pill). That way when you talk to the subjects about the experiment, there is no chance that you accidently tip them off  (with body language, or otherwise) to which type of pill they are getting. Furthermore, when you analyze the final results, you won’t have any temptation (subconscious or otherwise) to make the data come out a particular way (since you won’t know until you are done which subject was taking the aspirin and which was taking the sugar pill).

Unfortunately, if you carried out this experiment multiple times, you should expect to get slightly different results. After all, the people you would be able to recruit might be different and so might respond differently to the medicine. What’s more, even if you used the same people each time, the intensity of their headaches might vary from one 6 month period to the next, which could also influence how the results turn out.

But, if the results fluctuate randomly, that implies that sometimes, just by luck alone, the aspirin might seem to be effective even if it is not. Likewise, it might seem to be ineffective, even if it does work. So whatever it is that your experiment shows, how can you be sure you are really getting the right answer? Well, since chance is involved, total certainty is not possible. But a statistician could easily calculate for you the probability that you would get results (in favor of aspirin working) that are at least as strong as the ones that you got, if in fact aspirin is no more effective than the sugar pill. If this probability is large ,then based on your experiment you do not have sufficient evidence to conclude that aspirin is an effective treatment for headaches. If this probability is small (say, less than 5%), then aspirin very likely is effective. In order to increase the likelihood that the results of your test are conclusive, you would need only to increase the number of participants involved.

Hence, we see that in order to answer questions with a high degree of certainty, a well thought out methodology is necessary. Most elements of good study design become obvious when we reflect logically on the ways that data may mislead us. Whenever possible, experiments should be double blind with a placebo control. They should have large sample sizes, standardized dosages, a standardized (and predetermined) method for outcome measurement, and careful statistical analysis. Without all of these in place, experiments simply cannot be trusted.

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Should We Trust Our Gut? : The Idealization of Intuition and Instinct

Posted on December 30, 2009 by clockbackward

IT is common to hear advice that amounts to “going with your gut”, “trusting your instincts” or “following your intuition.” But these suggestions seem to indicate that the answers we arrive at through careful thought are sometimes (or perhaps usually) inferior to our immediate reactions. Consider the following representative quotes:

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.

Posted in Evolution, Philosophy, Skepticism, Truth | 1 Comment