Why read old philosophy?
I realize there's a (stereotypical) tendency for scientists and engineers to look down on philosophy - and I think this tendency colors this whole discussion to the extent that it almost borders on being a touchy subject.But a lot of the claims about the uselessness of philosophy in the modern world are probably based around the fact that, at least from the perspective of an Ancient Greek like Aristotle, there was no actual distinction between "science" and "philosophy".  It was all just sophia (wisdom) to him.  It was applying abstract inductive reasoning to arrive at universal truths.And this is patently obvious from simply reading Aristotle or the Pre-Socratics.  These writers routinely make what modern readers would consider outright scientific claims.  A lot of what Aristotle wrote is testable and falsifiable, and has indeed been falsified.  But to Aristotle there wasn't any inherent epistemological difference between reasoning about physics and reasoning about justice.  But today, we clearly separate these two spheres via empiricism - a method of thinking that wasn't really available to the Ancient Greeks, because it wouldn't be truly appreciated as part of a formal, scientific method, until the Medieval Arabs and later the European Renaissance thinkers really formalized it.So in that sense, it's understandable why some modern students might find reading Aristotle as silly as reading, say, a Medieval book about medicine or alchemy.I would argue, however, that Aristotle (and many of the ancient philosophers) are actually very valuable to read precisely because of their historical impact, and how their works shaped the course of human thought for millennia.  Aristotle's particular ideas about physics might be hopelessly wrong, but his thought processes and writings influenced Europe and the Middle East throughout the Middle Ages and beyond.  It is therefore critically important to have a good understanding of Ancient Greek philosophy if you are to have any hope of understanding the history of Western thought in general.