Heraclitus of Ephesus (530?-480? BCE), among the first of the Greek philosophers, considered the fundamental question of what it was that governed the essential nature of the universe. He taught that all things are in a constant state of flux, the striving of opposing forces one against the other: hot vs. cold, wet vs. dry. Fire consumes earth, transforming it into air or water, which solidifies into earth again. Nonethless, this multiplicity of opposites still forms a unified whole, which he called the logos, the Word or Truth (essentially the same concept appropriated by John the Evangelist in the prologue to his Gospel). The understanding of this logos, according to Heraclitus, is necessary for anyone to understand himself.
Parmenides of Elea (515?-450? BCE) was a younger contemporary of Heraclitus and an outspoken critic of his philosophy, but we do not know if the two ever met. We do know that Parmenides was a well-respected citizen of his hometown of Elea, in Lower Italy, and that as an old man he visited the young Socrates in Athens. Parmenides was a monist, believing that all things are one and that what appears to be in flux is merely an illusion. For him, the fundamental principles of existence were that "What is, is" and "What is not, is not". These seemingly self-evident statements led to profound conclusions. Since "What is not, is not", there is no such thing as nothing; consequently, no thing can ever be created, for it must have been created out of nothing; similarly, no thing can ever be utterly destroyed, for then it would enter into nothingness. But then, all things must be eternal and unchangeable.
What is most striking about this philosophy is its reliance on deductive logic as its underlying rhetorical force. Classical Greek philosophy was the first to realize the power of the rules of logic as a tool for common discourse; they understood that the passage of the mind from premise to conclusion by means of these rules was inescapably and inevitably true. The mind was compelled to assent to such deductions not because of the physical, political, or emotional power of the claimant over his audience, or even because of his oratory skill, but because of the universality and disinterested correctness of the logic of the argument.
Parmenides' finest student was Zeno (488-430? BCE), whose work is preserved in the writings of Aristotle (384-322 BCE), perhaps the greatest of all Greek philosophers. Zeno committed himself to defending Parmenides' philosophy by constructing a number of paradoxes, logical arguments that take the form of proof by contradiction (also known by its Latin equivalent reductio ad absurdum). Proof by contradiction works as follows: to show that a certain claim is false, one first supposes it is true, then argues deductively from this premise to a conclusion that is clearly false. It must follow that the premise could not have been true, which was what was to be argued in the first place. While Parmenides argues positively for why all things are one, Zeno argues negatively. His paradoxes are directed to the aim of showing why the existence of motion or change is impossible.
The text we will read is taken from
Aristotle's Physics and describes four of the paradoxes of Zeno.
(It is said that he devised some forty paradoxes in the defense of monism,
but no primary works of Zeno are extant today.) Be aware that these words
are not Zeno's but Aristotle's, and that Aristotle is no ally of Zeno.
Aristotle was an empiricist, one who believed that the strongest guide
to truth was one's own sense perceptions, and while he valued the use of
logic as a tool for understanding, he dismissed Zeno and the Monist school
as empty and absurd because he felt that they were mistaken in their deductions,
and worse, because they denied the clear perception of change in the world
around them. As you read the following, try to see beyond Aristotle's words
to what Zeno is really trying to say.
Read the text
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