Mathematics A Different Take on Differentiation I recently came across a tweet with a screenshot from a calculus book that defines the derivative with no mention of a limit. Not even Leibniz’s differentials have a home here. And although the definition is quite verbose, I found that it makes the derivative feel natural — tangible even.

Mathematics Ramsey Numbers: A Problem of Galactic Proportions When aliens attack, do you do the math or fight back? According to the prolific mathematician Paul Erdös, if aliens threaten to obliterate us if we can't calculate the Ramsey number for red six and blue six, then we better start fighting.

Mathematics The Reasonable Ineffectiveness of Defining Mathematics Mathematics is hard to define. But why?

Mathematics The Recovering Mathematician For the past few years, I've referred to myself as a recovering mathematician. Let me explain.