What... was the step that placed the Ionian cosmologists... above the [] level of the Maoris? ...[T]he real advance made by the scientific men of Miletos was that they left off telling tales. They gave up the hopeless task of describing what was, when as yet there was nothing, and asked instead what all things really are now.The great principle which underlies all their thinking, though it is first put into words by Parmenides, is that Nothing comes into being out of nothing, and nothing passes away into nothing. They saw, however, that particular things were always coming into being and passing away again, and from this it followed that their existence was no true or stable one. The only things that were real and eternal were the original matter which passed through all these changes and the motion which gave rise to them, to which was... added that law of proportion or compensation...

The truth is, that these writings of mine were meant to protect the arguments of Parmenides against those who make fun of him and seek to show the many ridiculous and contradictory results which they suppose to follow from the affirmation of the one. My answer is addressed to the partisans of the many, whose attack I return with interest by retorting upon them that their hypothesis of the being of many, if carried out, appears to be still more ridiculous than the hypothesis of the being of one.

Followers of Parmenides worked themselves into logical knots and mystic raptures over the rather blatant contradiction between point five and everyday experience.

The philosophy of Parmenides is a strange blend of mysticism and logic. It is mysticism, for its goal is not the gradual and cumulative correction of empirical knowledge, but deliverance from it through the instantaneous and absolute grasp of "immovable" truth. This is not the way of techne, but the way of revelation: it lies "beyond the path of men" (B. 1.27). Yet this revelation is itself addressed to man's reason and must be judged by reason. Its core is pure logic: a rigorous venture in deductive thinking, the first of its kind in European thought. This kind of thinking could be used against the world of the senses … This projection of the logic of Being upon the alien world of Becoming was Parmenides' most important single contribution to the history of thought, though it is seldom recognized as such. Without it, his doctrine of Being could have remained a speculative curiosity. With it, he laid the foundations for the greatest achievement of the scientific imagination of Greece, the atomic hypothesis.

One of Parmenides' merits is to have been the first philosopher who strove to handle general concepts like "being", "not-being", "knowing", "unity", "identity", in their systematic connection.

The path of speech (mythos odoio) (by Parmenides) contains within itself the path of day and that of night. It is no coincidence that Parmenides' poem comprises two parts. What exactly the second part contains and why it is so is an ancient philological and exegetical problem that we will not address here and which Plato already denounced in its ambiguity. In fact, it is not possible to separate being and speech without identifying them, and it is not possible to identify them without, ipso facto, separating them. The “simulation” (the simul) is immediate and structural. Human beings are simulators precisely because they are beings of truth. They cannot tell the truth without lying and vice versa. In this sense, they are beings of mediation, beings that stand in the middle, as you happily recall, that is, beings that ‘work’ to translate immediate experience into knowledge, or into a transferential process. God and nature do not work, but human beings do, first and foremost in naming the fruit of sexuality; it then places humans in the relational milieu of parents and children, brothers and sisters, offered, either really or symbolically, in sacrifice to God, that is, to the community of speakers. [...] The 20th century cannot exist without Sigmund Freud, psychoanalysis cannot exist without philosophy, at least in my opinion.

To prevent nothingness from being, Parmenides asserts that things are nothing. Parmenides, who first appears on the path of Day, which runs far from the path that the West has travelled, takes the first step along the path of Night in the West, the path along which things are thought and experienced as nothing. Parmenides is the tragic sower who sows both the seed of truth and the seed of Madness. (p. 77)

The history of the essence of nihilism (i.e., the belief that being is nothing) begins with Parmenides, who also affirms the eternity of Being and therefore the impossibility that it, in becoming, is not, i.e., is nothing. It is with Parmenides that the separation of beings from Being begins.

The position of Parmenides is unique because it is also the point of greatest contact with the East.[...] Parmenides' radical solution is this: becoming no longer threatens, it cannot be harmful because it does not exist. [...] Everything that is distressing, terrible and horrendous in the world is illusion; this is the meaning of Parmenides' “'doxa”'. Well, this is also the path taken by the East: the “”Vedas“”, the “”Upanishads“”, the Buddhist revival of Brahmanism are all great themes that converge on this point: man is unhappy because he does not know he is happy, because he does not know that pain is outside him, and that he is a pure gaze that is not contaminated by the pain that passes before him, just as the mirror is not contaminated by the image reflected in it.

If I accede to Parmenides there is nothing left but the One; if I accede to Zeno, not even the One is left.