Used the Wason card selection task, and various invented scenarios involving the breaking of social rules.
In the original Wason expt:
But 80% of undergraduates get it wrong. Simplified examples (not used by Cosmides) are given below.
Bus pass 1
IF SOMEONE HAS OUR PASS THEN THEY TRAVEL ON OUR BUS
1st overhead. Logically this means that you should turn over having the pass and not going on the bus. It is not “if and only if” and therefore logicians would say the rule allows people to travel on the bus without a pass. But most people would ‘look for cheaters’.
IF SOMEONE TRAVELS ON OUR BUS THEN THEY HAVE OUR PASS
2nd overhead. This way around almost everyone would get it right, since the logically correct answer for exception to the rule is someone travelling on a bus without a pass.
Cosmides (1989) argued that detailed experimental results of this general kind should be explained in terms of the influence of natural selection on human reasoning — the idea is that human mental capacities are adaptations to the demands of living in hunter-gatherer societies, and not naturally suited to the more abstract rules of the propositional calculus found in textbooks of logic. The phrase used in the online “Primer” on Evolutionary Psychology is that “Our modern skulls house a stone age mind”.
But, although there is support for the finding that in experimental contexts human subjects tend to be bad at logic, not many psychologists are convinced that this makes the stone ages relevant (e.g. Fodor, 2000). Empiricists can argue that most human subjects have had a lifetime of learning about rules and rule-breaking, but little experience of abstract logic.References
Cosmides, L. (1989) The logic of social exchange: Has natural selection shaped how humans reason? Studies with the Wason selection task. Cognition, 31, 187-276.
Duchaine, B., Cosmides, L., & Tooby, J. (2001). Evolutionary psychology and the brain. Current Opinion in Neurobiology, 11(2), 225-230. (online in ScienceDirect).
Fodor, J. (2000). Why we are so good at catching cheaters. Cognition, 75, 29–32.
Wason, P.C. (1966). Reasoning. In B.M. Foss (Ed.), New horizons in psychology. Harmondsworth: Penguin. pp. 135-151.
See also a discussion with examples in The Philosophers Magazine on the Internet.
Some other external links refering to the Wason card selection task –