In March, I was in Paris for the International Convention of Psychological Science, one of the most prestigious gatherings in cognitive science. I listened to talks from my field, human reasoning, but I also enjoyed those on ethology, because I find studies on non-human animals, from turtles to parrots, fascinating. Despite their typically small sample sizes, I found the scientific reasoning in the animal-studies talks sounder, and their explanations richer, than the work I heard on human reasoning.
The reason is simple: Ethologists evaluate their experimental paradigm, or set-up, in light of its ecological validity, or how well it matches natural surroundings. An animal’s true habitat, and its evolutionary history, have always centered the discussion. In contrast, most experimental paradigms in human reasoning, such as the Cognitive Reflexion Test (CRT) or syllogisms, are based on logic or mathematics. One of the most famous tasks of the CRT is the bat and ball problem: A bat and a ball cost $1.10. The bat costs $1 more than the ball. How much does the ball cost? Most participants fail at this task. The correct answer is not 10 cents, but 5 cents. Perhaps the ultimate tool psychologists use to study reasoning is the syllogism: For example, “Major premise: All men are animals. Minor premise: Some animals are aggressive. Conclusion: Some men are aggressive.” (Does this conclusion follow?)