Matt Lehrer

This assumption—that understanding a system’s constituent parts means we also understand the causes within the system—is not limited to the pharmaceutical industry or even to biology. It defines modern science. In general, we believe that the so-called problem of causation can be cured by more information, by our ceaseless accumulation of facts. Scientists refer to this process as reductionism. By breaking down a process, we can see how everything fits together; the complex mystery is distilled into a list of ingredients. And so the question of cholesterol—what is its relationship to heart disease?—becomes a predictable loop of proteins tweaking proteins, acronyms altering one another. Modern medicine is particularly reliant on this approach. Every year, nearly $100 billion is invested in biomedical research in the US, all of it aimed at teasing apart the invisible bits of the body. We assume that these new details will finally reveal the causes of illness, pinning our maladies on small molecules and errant snippets of DNA. Once we find the cause, of course, we can begin working on a cure.

The problem with this assumption, however, is that causes are a strange kind of knowledge. This was first pointed out by David Hume, the 18th-century Scottish philosopher. Hume realized that, although people talk about causes as if they are real facts—tangible things that can be discovered—they’re actually not at all factual. Instead, Hume said, every cause is just a slippery story, a catchy conjecture, a “lively conception produced by habit.” When an apple falls from a tree, the cause is obvious: gravity. Hume’s skeptical insight was that we don’t see gravity—we see only an object tugged toward the earth. We look at X and then at Y, and invent a story about what happened in between. We can measure facts, but a cause is not a fact—it’s a fiction that helps us make sense of facts.

There are a few things that seem to be related to people’s attitude that Psychology is easier than other sciences. For one, children think it would be easier to learn about aspects of Psychology than to learn about the natural sciences. They are also more sure that adults would know how things work in Psychology than in the natural sciences.

The authors did rule out one explanation. They found that children and adults were no better at distinguishing between facts that are true and false in psychology and in other sciences. That is, people don’t believe that Psychology is easier because they actually know more about it. They believe that Psychology is an easier science than the natural sciences because it feels easier.

A key aspect of thinking about Psychology is that we all have minds. We all have conscious experiences of what it is like to think. Those experiences give us intuitions about the way our thought processes work. Even though those intuitions are often misleading, it feels like a good scientific explanation for those thought processes are just beyond our grasp.

The authors point out that this facet of Psychology has some important practical consequences. For example, judges in legal trials are often much less likely to allow Psychologists to give expert testimony on the workings of the mind than they are to allow other scientists to give expert testimony. The judges see the relevant Psychology as part of a juror’s common sense.

Excellent article, via @timoreilly.