Nick: Nice spin! :) Context would be important if Eliezer had not asserted as a given that many, many experiments have been done to preclude any influence of context. My extremely limited experience and knowledge of psychological experiments says that there is a 100% chance that such is not a valid assertion. Imagine a QA engineer trying to skate by with the setups of psych experiments you have run in to. But, personal, anecdotal experience aside, it’s real easy to believe Eliezer’s assertion is true. Most people might have a hard time tuning out context, though, and therefore might have a harder time, both with conjunction fallacy questionnaires and accepting Eliezer’s assertion.
g: Yes, keeping in mind that I would be first in line to answer C, myself!
Choice (B) seems a poster boy for “representation”. So, that a normal person would choose B is yet another example of this, “probability” question not being a question about probability, but about “representation”. Which is the point. Why is it hard to imagine that the word, “probable” does not mean, in such questions’ contexts, or even, perhaps, in normal human communication, “probable” as a gambler or statistician would think of its meaning? Or, put another way, g, “who try to answer the question they’re asked rather...” is an assumptive close. I don’t buy it. They were not asked the question you, me, Eliezer, the logician or the autistic thought. They were asked the question that they understood. And, they have the votes to prove it. :)
So far as people making simple logical errors in computing probabilities, as is implied by the word, “fallacy”, well, yeah. Your computer can beat you in both logic and probabilities. Just as your calculator can multiply better than you.
Anyway, I believe that the functional equivalent of visual illusions are inherent in anything one might call a mind. I’m just not convinced that this conjunction fallacy is such a case. The experiments mentioned seem more to identify and wonderfully clarify an interesting communications issue—one that probably stands out simply because there are, in these times, many people who make a living answering C.