The appellation ’pre-Socratic’ is a little misleading, since it refers to a number of philosophers who were contemporaries of Socrates, and excludes Protagoras. It actually refers more to a brand of philosophy, dominated by an interest in the Natural world, mathematics, form, etc., and a quest to understand origins, mechanics, and to formulate hypotheses about the world. The ideas of Socrates, developed by Plato, instead allotted much more importance to social, political, and moral questions, and in doing so consciously reacted against the ’pre-Socratics’.
For our purposes, the most important thing about the pre-Socratics is (i) the extent to which they anticipated and
molded the later Greek ideas (indeed, some of the key ideas of Plato started from Heraclitus and Parmenides on the philosophical side, and from the earlier Pythagorean work in mathematics); and (ii) the fact that their ideas, in many ways, represent the very beginnings of what we now call scientific inquiry. For this latter reason alone they deserve our attention: although the beginnings of any really new area of human thought are always hard to understand, being inevitably somewhat disorganized, they are the crucial leaps that have brought us to where we are now. One learns a great deal by studying such leaps.
