Until the publication of the Phaedo, Plato had been working in the shadow of Socrates. He was a Socratic, a follower of the idiosyncratic barefoot philosopher—an unlikely one, to be sure: rich, haughty, ambitious, well-educated. He seems to have emerged from the group of Socrates’ supporters in the first place because of his literary genius. He could make Socrates come alive on the page. He could make every inquiry a suspenseful drama in which the self-effacing gadfly demolished the pretensions of sophists and self-appointed wise men. He could turn philosophical debate into a comedy, an almost-tragedy, or an apology (that is: a defense). He could make the reader laugh or weep or applaud the life of an unlikely character, an anti-hero.
But Plato was not only the most gifted author of the Socratic movement, but the most insightful philosopher. He alone seems to have grasped the subtlety and power of a theory hidden behind Socrates’ apparently destructive questioning. While other Socratics saw him as a kindly mentor or an inspired but ignorant guide, Plato saw the method in his madness: Socrates had a well-thought-out belief system, a philosophy. His inquiries were not acts of deconstruction, but of elimination, designed to leave the true philosophy as the last theory standing, and ultimately to reveal the rationality and sovereignty of virtue.
But Plato was not just a follower of Socrates. As we first glimpse in the Phaedo, Plato could go beyond Socrates to build an edifice of theory in support of Socrates’ moral precepts. What was missing in Socrates was the infrastructure necessary to uphold a moral theory. What were moral truths without a firm foundation? If there were no permanent realities, such as the Heracliteans and some sophists claimed; if there was, in consequence, no certain knowledge; if there were no enduring subjects of knowledge; if there were, consequently, no truth, no meaning, no purpose, how could there be right and wrong, good and evil?
In the Phaedo, Plato posits the existence of ideal entities, the Forms, such as Equality, Beauty, and Virtue. He posits the existence of immortal souls, which he argues for at length in the present dialogue. He accepts a belief in reincarnation, presented in Orphic and Pythagorean religious communities, and imagines an afterlife in the underworld and the upper heaven. He defends also a theory of knowledge, the Theory of Recollection, in which basic truths learned in previous incarnations provide a foundation for secure knowledge. He sketches a new cosmology in which the earth, sun, moon, and stars are part of a divine design which promotes morality and goodness and provides a home and a training ground for immortal souls.
But what, exactly, are the Forms? Plato has Socrates’ followers accept them eagerly, and he allows Socrates to offer examples of them: Equality, Beauty, Goodness.[25] He tells us that they are “uniform” (monoeidēs),[26] which seems at least to imply that each Form has one and only one character, that it represents one and only one property: for example, equality, or beauty, or goodness. Plato obviously posits a plurality of Forms to account for the plurality of characters of things. The Forms are, according to Plato, completely changeless in themselves, and apparently eternal. For something that is utterly changeless is in some sense outside of time, so not everlasting through time, but eternal outside of time. But while it is no doubt heartwarming to believe in a world of eternal ideal Forms, Plato does not here, at least, give us a reason for their being ideal in a moral or value-theoretical sense. If there is a Form for every property, then why not a Form of Inequality, Ugliness, Evil? If, on the other hand, there are Forms only if positive states of being, how are we to understand the existence in the world of inequality, ugliness, and evil?
This raises a Population Problem for the Theory of Forms. Of just what things are there Forms? Only of positive properties, as already suggested? Of only characteristics, or of objects too, such as a Form of Dog and Cat and Human? Are there Forms of man-made objects such as of Bed and Table and Chair? Is there a form of City or City-State? As Plato will ask in a later dialogue, are there Forms of disgusting things like Hair and Mud and Dirt?[27]
Furthermore, if souls are immortal, when did they come to be, or did they always exist? If they always existed, why did they have to learn anything in previous lives, since there was no first life? If they always existed, and, as Plato depicts in the Phaedo, the most worthy of them are able to cease undergoing reincarnations, graduating to philosophical Nirvana, why have not all souls (except some incurably bad ones that are consigned to remain in hell) already graduated and thus ceased to inhabit the world of change?[28]
From now on, most of Plato’s dialogues will assume or explicitly acknowledge the Forms, Immortality of Soul, Reincarnation, and Recollection. Plato will engage with many of these issues, though never in a rigorous and systematic way. Plato will emerge as a complete philosopher, with theories of (almost) everything, but not as a systematic philosopher who will answer (almost) every question that his philosophy raises. He will not hesitate to extend his account of the cosmos into the realms of speculation and mythology, for the sake of the edification of his audience, even if he offers disclaimers about the details.[29]
What, then, are Forms, and what difference do they make to us mortals—or rather, to us immortal souls confined to mortal bodies—who live in a world of flux?
[25] Plato Phaedo 65d, 74c, 76e-77a.
[26] Plato Phaedo 78d; similar to the soul, 80a-b.
[27] Plato Parmenides 130c.
[28] Plato Phaedo 113d-114c.
[29] Plato Phaedo 114d-115a.