One must ask if the investigators of this study selected the correct faculty for examination. (I kid, this is embarrassing)
As a mathematician, I was primed with the knowledge that a large fraction of a mathematics department failed this test. I looked it up on Wikipedia, didn't spoil the answer, and thought damn hard before unfolding the "solution" section. I was relieved to see my answer therein. I do wonder if the students and staff were primed to think about this as a logic puzzle, or if they simply went with a gut answer. Because in my experience, that makes loads of difference in how people of all stripes, mathematicians included, respond to challenging questions.
My gut response was to flip an extra card, for what that's worth. Secondary consideration took a couple of seconds, and I spent another thirty convincing myself that I was correct.
As a mathematician, I was primed with the knowledge that a large fraction of a mathematics department failed this test. I looked it up on Wikipedia, didn't spoil the answer, and thought damn hard before unfolding the "solution" section. I was relieved to see my answer therein. I do wonder if the students and staff were primed to think about this as a logic puzzle, or if they simply went with a gut answer. Because in my experience, that makes loads of difference in how people of all stripes, mathematicians included, respond to challenging questions.
My gut response was to flip an extra card, for what that's worth. Secondary consideration took a couple of seconds, and I spent another thirty convincing myself that I was correct.