Aristotle, Objectivity, and the Unmoved Mover

Abstract

In the fragments cited above, we sense the philosophical situation in the cosmopolitan center that was Athens in the fifth and fourth centuries BCE, where ideas from the entire Mediterranean encountered one another, leaving some philosophers skeptical and others committed to clarifying how one might know with certainty. Is human intellect the measure of all things? Is knowledge only a combination of opinion and persuasion?

Man is the measure of all things: of things that are, that they are; of things that are not, that they are not. (Protagoras 480-411 BCE)¹

… since in fact men have little ability to remember the past, observe the present, or foretell the future, speech works easily; with the result that most speakers on most subjects offer only opinion .… But opinion is delusive and inconstant, and those who rely on it run grave risks. (Gorgias fifth-fourth century BCE)²

Although all of them want to find some entity by which everything in the universe can be explained, they cannot agree on how to name that entity. One of them calls it air, another fire, another water, and another earth; each of them trying futilely to adduce evidence to substantiate his own account. The fact that they give different answers. although making the same kind of inquiry, shows how faulty their knowledge must be. (Hippocrates of Cos 460-390 BCE)³