Parmenides was the founder of the Eleatic school and one of the most important pre-Socratic philosophers. He lived in the 5th century BC (ca. 515-450 BC) in Elea, a Greek colony in southern Italy. He had a huge influence on later thinkers such as Plato, Aristotle, Spinoza and the great Thomas Aquinas, who wrote "ex nihilo nihil fit" - from nothing comes nothing).

But what did Parmenides do?

Well, he was perhaps the first to put pure reason at the center of philosophy – rejecting sensory and empirical knowledge as illusory and full of contradictions. Parmenides was the first to fully trust the power of the mind even when it led to conclusions radically contrary to everyday experience. His intellectual courage consisted in the fact that he did not hesitate to question the most basic beliefs about reality, if logical consequence required it. He made a transition from the study of nature based on observation to a purely logical, rational study of reality. He entered the space of abstract thinking , which is no longer based on what "seems" but on what must be if we want to think without contradiction.

He entered the realm of pure philosophical abstraction. His philosophy is one of the first examples of pure abstract thinking in the history of human thought.

So let's consider and analyze his most popular statement.