NATURAL PHILOSOPHY

Until comparatively recently, the relationship between philosophy and physics was reasonably amicable. As William Simpson has put it: “Physics was part of natural philosophy, and students of physics were trained in philosophical texts and forms of argumentation; they were men of letters as well as numbers” (2012).

In the beginning, philosopher and physicist were often one and the same person. It would have seemed odd to ancient Greek philosophers that they should refrain from speculating about the nature of the physical world. Most of the great Presocratic philosophers had their own theories of the character of fundamental stuff of which the world was made. In Aristotle's thought, there was a brisk and fertile trade between his philosophy and his scientific observations. Even Plato, who sought to look past or through the world as revealed to the senses and empirical investigation, and sought the true nature of things in argument guided by reason rather than in sense experience, was persuaded of the importance of mathematics: “Let no one ignorant of geometry enter here” is said to have been inscribed above the entrance to his Academy; and he asserted that “he is unworthy of the name of man who is ignorant of the fact that the diagonal of a square is incommensurable with its side”.

Of course, there was a huge disproportion between the quantity of data and the scope of these natural philosophers' theories about the natural world: argument trumped observation.