I want to note that for a mathematician, logic is used to describe things that are ‘always true’. In its biological origins a logical proposition was useful when it was right ‘somewhat more than you might otherwise expect’. We survived on rules of thumb and something very much like the mathematician’s logic was critical to this. Early on the useful propositions were built into our genes. Later on they became dynamic products of our nervous system.

I find it remarkable that one sort of structure serves these two purposes so well—in particular that the mathematician’s instance on no exception morphs this fuzzy discipline to yield beautiful and useful constructs. It has all to do with patterns, from the shape of a leaf to the form of a mathematical group.

counting, language, modal logic, Evolution of Information Mechanisms

I just heard this guy talk and I doubt that I have anything to say that he doesn’t say better!