Does anything survive?

The Phaedo does not posit survival, it argues for it, through four linked proofs: the generation of opposites, recollection which presupposes knowledge prior to birth, the soul's affinity with the simple and indestructible intelligible, and finally the essence argument, the soul that carries life within it being unable to admit its contrary. The reasoning rests on the dualism of soul and body: what is simple does not decompose, hence does not perish. Death then ceases to be annihilation and becomes the soul's passage toward the intelligible, and philosophy itself, as detachment from the body, is its anticipated rehearsal.

Those who practise philosophy in the right way are in training for dying.Phaedo, 67e

Phaedo, 64a, 102a-107b · Republic, X, 614a-621d (myth of Er)

The Timaeus presents a Demiurge, a good craftsman-god who orders the world by looking to the Forms as models; the Laws assert the existence of gods and providence against atheism. This rational, impersonal theism, with no creation ex nihilo and no single God in the monotheist sense, holds the score back from the extreme.

Timaeus, 28a-30c · Laws, X, 885b-907d

If the soul knows the eternal and unchanging intelligible, it is because it is akin to it: what grasps the simple must itself be simple. From this kinship Plato concludes that the true self is not the bodily composite but the soul, an immaterial substance that preexists birth and survives death. The Alcibiades sharpens the divide: a person is neither the body nor the compound of both, but "is" the soul, the body being merely an instrument it uses. This identification of the person with a separable substance, against any self bound up with embodiment, grounds the whole of Platonic psychology and eschatology.

Phaedo, 78b-80b · Alcibiades, 129e-130c

Since the soul is corporeal and is born, grows and ages with the body, it dissolves with it: all feeling then ceases, and a subject who is no more can suffer no evil. Death is therefore nothing to us, a conclusion Epicurus already held; but Lucretius devotes the whole of book III to it and makes of it a long consolation, multiplying proofs of the soul's mortality and the symmetry argument: we do not grieve over the nothingness before our birth, so why dread the one after our death, which resembles it in all things? To wish to survive is to contradict oneself, for the dead will have neither lack nor regret. The consolation widens into a rejoinder spoken by nature herself, who reproaches the living for their ingratitude and their thirst to endure.

Death, then, is nothing to us and touches us not at all, since the nature of the mind is held to be mortal.On the Nature of Things, III, 830-831

On the Nature of Things, III, 417-829 (the mortal soul; death is nothing to us) · On the Nature of Things, III, 830-1094 (the symmetry argument; the diatribe of Nature)

Lucretius does not deny that the gods exist: made of subtle atoms, they lead an immortal and perfectly peaceful life in the intermundia, with no care for ours. But he draws a radical consequence: a blessed being has neither anger nor favour, so no providence governs the world, no god made it or rewards and punishes. The proof lies in the very spectacle of nature, too full of flaws to be the work of a divine power. This position is therefore not atheism, of which he was accused, but a theology without providence: the gods neither create nor govern anything, and its edge is polemical: so much wrong could religion prompt, it is religion, not impiety, that is the true evil to be fought.

So much wrong could religion prompt.On the Nature of Things, I, 101

On the Nature of Things, I, 62-101 (religion as source of crimes, the sacrifice of Iphigenia) · On the Nature of Things, V, 146-234 (the gods of the intermundia; the world too flawed to be divine)

The mind (animus, the seat of thought) and the vital breath (anima, spread through the whole body) are not a simple or immortal substance but a compound of very small, very mobile atoms mingled with the flesh. Born with the body, this bundle comes apart when the assemblage breaks up: the self has no identity beyond its material composition, and there can be no transmigration. Lucretius adds an argument of his own: even were our atoms to gather again after ages, it would not be us, for the thread of memory would be severed. This is a bundle theory.

On the Nature of Things, III, 94-322 (animus and anima, the nature of the soul) · On the Nature of Things, III, 843-861 (were our atoms to reassemble, it would no longer be us)