Plato (427–347 BC)

13. Phaedo

The departure point for Phaedo’s consideration of the fate of the soul after death is very close to that idea of love as desire for wisdom which Diotima offers at the start of her speech in Symposium. For Socrates starts with the pursuit of wisdom, which he claims is really a preparation for death. This is because it consists of an attempt to escape the restrictions of the body so far as is possible, and to purify the soul from preoccupation with the senses and physical desires so that it can think about truth, and in particular about the Forms, which are accessible not to sense perception but only to thought. Pure knowledge of anything would actually require complete freedom from the body. So given that death is the separation of soul from body, the wisdom philosophers desire will be attainable in full only when they are dead. Hence for a philosopher death is no evil to be feared, but something for which the whole of life has been a training. The unbearably powerful death scene at the end of the dialogue presents Socrates as someone whose serenity and cheerfulness at the end bear witness to the truth of this valuation.

Symposium implied that a long process of intellectual and emotional reorientation was required if someone was to achieve a grasp of the Form of Beauty. Phaedo has sometimes been thought to take a different view: interpreters may read its argument about recollecting Forms as concerned with the general activity of concept formation in which we all engage early in life. In fact the passage restricts recollection of Forms to philosophers, and suggests that the knowledge they recover is not the basic ability to deploy concepts (which Plato seems in this period to think a function of sense experience), but hard-won philosophical understanding of what it is to be beautiful or good or just. The interlocutors voice the fear that once Socrates is dead there will be nobody left in possession of that knowledge; and the claim that pure knowledge of Forms is possible only after death coheres with the Symposium account very well, implying as it does that the path to philosophical enlightenment is not just long but a journey which cannot be completed in this life.

The proposal that the soul continues to exist apart from the body after death is immediately challenged by Socrates’ interlocutors. Much of the rest of Phaedo is taken up with a sequence of arguments defending that proposal and the further contention that the soul is immortal, pre-existing the body and surviving its demise for ever. The longest and most ambitious of these arguments is the last of the set. It consists in an application of the method of hypothesis, which is explained again in a more elaborate version than that presented in Meno. The hypothesis chosen is the theory of Forms, or rather the idea that Forms function as explanations or causes of phenomena: beautiful things are beautiful by virtue of the Beautiful, large things large by virtue of the Large, and so on. Socrates is made to represent his reliance on this apparently uninformative or ’safe and simple’ notion of causation as a position he has arrived at only after earlier intellectual disappointments: first with the inadequacies of Presocratic material causes, then with the failure of Anaxagoras’ promise of a teleological explanation of why things are as they are (see Anaxagoras §4).

He soon goes on to argue however that the hypothesis can be used to generate a more sophisticated model of causation. Instead of proposing merely that (for example) hot things are hot by virtue of the Hot, we may legitimately venture the more specific explanation: ‘Hot things are hot by virtue of fire’, provided that it is true that wherever fire exists, it always heats things in its vicinity, being itself hot and never cold. After elaborating this point Socrates is ready to apply the model to the case of life and soul. By parity of reasoning, we may assert that living things are alive not just in virtue of life, but in virtue of soul, given that wherever soul exists it makes things it occupies alive, being itself alive and never dead. From this assertion there appears to follow the conclusion whose derivation is the object of the exercise: if soul is always alive and never dead, it must be immortal (that is, incapable of death) and so imperishable.

Phaedo, like Republic, ends with a sombre myth of last judgment and reincarnation, designed primarily to drive home the moral implications of Plato’s distinctive version of soul–body dualism. It reminds us of the Pythagorean origins of the doctrine of the immortality of the soul. Yet the Platonism of Phaedo owes a great deal also to the metaphysics of Parmenides. Both here and in Symposium the characterization of Forms as simple eternal beings, accessible only to thought, not the senses, and the contrast both dialogues make with the changing and contradictory world of phenomena, are couched in terms borrowed from Parmenides and the Eleatic tradition which he inaugurated. Platonism can accordingly be seen as the product of an attempt to understand a fundamentally Socratic conception of philosophy and the philosophical life in the light of reflection on these two powerful Presocratic traditions of thought, using the new methodological resources made available by geometry.