Reading: Plato's Thought

An Introduction To Plato’s Thought

What follows here is the summary of Plato’s thinking that has been put together on a website called the Philosophy Pages by Garth Kemerling which are licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

What follows is only a short excerpt of all that Mr. Kemerling has on the site re Plato. It is what I wanted to have you be aware of so that you have a small idea of Plato. More will follow in the following activities.

The Cycle of Opposites

The first argument is based on the cyclical interchange by means of which every quality comes into being from its own opposite. Hot comes from cold and cold from hot: that is, hot things are just cold things that have warmed up, and cold things are just hot things that have cooled off. Similarly, people who are awake are just people who were asleep but then woke up, while people who are asleep are just people who were awake but then dozed off.

But then, Plato argues by analogy, death must come from life and life from death. (Phaedo 71c-d) That is, people who are dead are just people who were alive but then experienced the transition we call dying, and people who are alive are just people who were among the dead but then experienced the transition we call being born. This suggests a perpetual recycling of human souls from the realm of the living to the realm of the dead and back.

If this is an accurate image of reality, it would certainly follow that my soul will continue to exist after the death of my body. But it also supposes that my soul existed before the birth of my body as well. This may seem like an extravagant speculation, but Plato held that there is ample evidence of its truth in the course of ordinary human life and learning.

The Forms

As Socrates had proposed in the Meno, the most important varieties of human knowledge are really cases of recollection. Consider, for example, our knowledge of equality. We have no difficulty in deciding whether or not two people are perfectly equal in height. In fact, they are never exactly the same height, since we recognize that it would always be possible to discover some difference—however minute—with a more careful, precise measurement. By this standard, all of the examples we perceive in ordinary life only approach, but never fully attain, perfect equality. But notice that since we realize the truth of this important qualification on our experience, we must somehow know for sure what true equality is, even though we have never seen it. (Phaedo 75b)

Plato believed that the same point could be made with regard to many other abstract concepts: even though we perceive only their imperfect instances, we have genuine knowledge of truth, goodness, and beauty no less than of equality. Things of this sort are the Platonic Forms, abstract entities that exist independently of the sensible world. Ordinary objects are imperfect and changeable, but they faintly copy the perfect and immutable Forms. Thus, all of the information we acquire about sensible objects (like knowing what the high and low temperatures were yesterday) is temporary, insignificant, and unreliable, while genuine knowledge of the Forms themselves (like knowing that 93 - 67 = 26) perfectly certain forever.

Since we really do have knowledge of these supra-sensible realities, knowledge that we cannot possibly have obtained through any bodily experience, Plato argued, it follows that this knowledge must be a form of recollection and that our souls must have been acquainted with the Forms prior to our births. But in that case, the existence of our mortal bodies cannot be essential to the existence of our souls—before birth or after death—and we are therefore immortal.

Immortality of the Soul

Use of the dialogue as a literary device made it easy for Plato not only to present his own position (in the voice of Socrates) but also to consider (in the voices of other characters) significant objections that might be raised against it. This doesn't mean that philosophy is merely an idle game of argument and counter-argument, he pointed out, because it remains our goal to discover the one line of argument that leads to the truth. The philosopher cautiously investigates every possibility and examines every side of an issue, precisely because that increases the chances of arriving eventually at a correct account of reality.

Thus, Simmias suggests that the relationship between the soul and the body may be like that between musical harmony and the strings of a lyre that produces it. In this case, even though the soul is significantly different from the body, it could not reasonably be expected to survive the utter destruction of that physical thing. (This is an early statement of a view of human nature that would later come to be called epiphenomenalism.) But Socrates replies that this analogy will not hold, since the soul exercises direct control over the motions of the body, as the harmony does not over those of the lyre. Plato's suggestion here seems to be that it would become impossible to provide an adequate account of human morality, of the proper standards for acting rightly, if Simmias were right.

Cebes offers a more difficult objection: what if the body is like a garment worn by the soul? Even though I continue to exist longer than any single article of my clothing does, there will come a time when I die, and some of my clothes will probably continue to exist. In the same way, even if the argument from opposites has shown that the soul can in principle outlast the life of any particular human body, there might come a time when the soul itself ceases to exist. Even if there is life after death, Cebes suggests, the soul may not be truly immortal.

In response to this criticism, Plato significantly revised the argument from opposites by incorporating an additional conception of the role of the Forms. Each Form, he now maintains, is the cause of all of every particular instance that bears its name: the form of Beauty causes the beauty of any beautiful thing; the form of Equality causes the equality of any pair of equal things; etc. But then, since the soul is living, it must participate in the Form of Life, and thus it cannot ever die. (Phaedo 105d) The soul is perfectly and certainly imperishable, not only for this life, but forever.

Despite the apparent force of these logical arguments, Plato chose to conclude the Phaedo by supplementing them with a mythical image of life after death. This concrete picture of the existence of a world beyond our own is imagined, not reasoned, so it cannot promise to deliver the same perfect representation of the truth. But if we are not fully convinced by the certainty of rational arguments, we may yet take some comfort from the suggestions of a pleasant story.

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