The myth of scientific infallibility

Blood lettingI’ve never liked Woody Allen. His nebbish-centered humor never worked for me and, as he aged in his films, I found distasteful his young leading ladies. I really didn’t need to see him play out his creepy romantic fantasies before my eyes, especially if I was paying for the privilege of seeing it.

Having said that, there’s one scene in a Woody Allen movie that I’ve always found to be not just funny but wise:

I thought of that scene when I read Charles Krauthammer’s column today about the various theories that held sway in the scientific world over the years, and which were subsequently proven to be terribly wrong.  For an elegant writer like Krauthammer, it’s a an easy step from reminding readers about blood-letting to telling them about all the economic fallacies underlying Obamacare’s passage.

The hypothesis fallacy; or please explain to me why EVERY scientific experiment (whether hard or social) needs a hypothesis

Scientist

Bear with me here, because I’m about to prove how simplistic and primitive my mind is.  I need you all to help enlighten me.

Some high school students I know got an assignment to set up and complete an experiment.  Some of the experiments they came up with include looking at plant growth under different circumstances, or rust development under different circumstances, or human responses to certain stimuli.  This strikes me as a very sensible project for budding young scientists.

Plant growth experiment

My confusion arises from the fact that the students are required, as part of setting up the experiment, to include a hypothesis — or, in other words, they have to begin the experiment with an assumption about its outcome.  For example, a student measuring the effect of different fertilizers on otherwise identically situated plants, in addition to establishing the controls and variable(s), must also announce before starting the experiment that she believes that the more expensive fertilizers will work better.  Then, she’s supposed to see whether the data she collects supports this hypothesis.  (I.e., she proves or disproves her hypothesis.)

Here’s my problem:  I don’t understand why there is a scientific virtue to going into an experiment with a pre-determined conclusion.  It seems to me that it’s much more intelligent, in most, if not all cases, to go in with a question, and then to create an experiment that has sufficient controls to answer that question and that question alone.  My hostility to the hypothesis as a prerequisite arises because I suspect that a pre-determined hypothesis risks affecting the outcome.  Sherlock Holmes thought this too:

Sherlock Holmes by Sidney Paget

It is a capital mistake to theorize before you have all the evidence. It biases the judgment.

Exactly.  The scientist who has decided in advance that spending more on fertilizer results in better plant outcomes may subconsciously lavish a little more care or do things a little differently with the plant getting the good fertilizer.  The experiment is less likely to be tainted by the scientist’s biases if the scientist begins by asking “Which fertilizer is better?” rather than announcing “I think the more expensive fertilizers are better.”

Birth Control Pills

This is not just an idle question about high school projects.  I’ve noted the disdain that I have for Bay Area breast cancer studies that assume the culprit for the unusually high cancer rate in the Bay Area arises from too much bacon (evil factory farming) or from power lines (evil global warming).  One could just as easily announce that the hypothesis is that Bay Area women have high breast cancer rates because they get too much radiation from too many mammograms, or they have too many abortions (at too young an age), or they delay childbearing for too long, or they overuse of the Pill, etc.  If my study focused as narrowly on my assumptions, as these heavily Leftist studies focus on their assumptions, both studies would show that women who had done one or more of those things had higher cancer rates.

Establishing these almost random correlations (given the ridiculously biased parameters underpinning the various hypotheses) wouldn’t prove causation; instead, they would just prove that the scientist’s own prejudices forced the data down a narrow pathway.  Doesn’t it make more sense to find out about everything from diet, to environment, to lifestyle/sexual choices, and then, a la Sherlock Holmes, to see where the facts lead?

Global warming

This same “hypothesis fallacy,” for want of a better phrase, strikes me as one of the major problems with the whole global warming hysteria.  Various Leftists advanced the hypothesis that fossil fuels (which we know can contribute to pollution, and that Leftists believe give an unfair economic advantage to the First World) are evil, and then they set about proving their evil-ness.  If climate change is a genuine concern, wouldn’t it have made more sense to start with the question — “what’s going on?” — than to start with the answer — “Fossil fuels are changing our climate.”  After all, if your set-in-stone hypothesis isn’t even in the ball park, it means that your experiments are not only worthless, but they’ve also managed to ignore other, more relevant, data.

I understand that the hypothesis is a standard requirement for scientific experiments and has been since the Enlightenment.  I’ve explained, with a little help from Sherlock Holmes, why I think the hypothesis requirement taints, rather than advances, science.  Now that I’ve acquainted you with the contents of my brain, can you please explain to me why the scientific community is correct, and why Sherlock Holmes and I are wrong.