Yesterday, a friend reminded me of one of the most evil of all brain teasers, which is the question:

“Physiologically speaking, what is a thought?

It’s interesting that as happy as one might be to provide a smarty-pants, toss off answer like “it is a set of biochemical interactions in the brain“, this would in fact not be correct.

Feel free to provide the correct answer below; we’ll be back next Friday with an explanation.