When Plato's name is turned into an adjective to modify a noun, it is usually attached to either "love" or to "idea." We hear scholarly people say: "That's only a Platonic idea and it has nothing to do with reality."
What underlies the derogatory thrust of the phrase "Platonic idea" is, of course, Plato's theory of ideas, which is hardly a commonsense doctrine that most people readily embrace. On the contrary, when they understand it, they find it runs counter to t heir commonsense view of the way things are. But it is far from being wholly wrong. Of the two central tenets of Plato's theory of ideas, one was right and the other wrong.
Let us begin with what was wrong about it. For Plato, there were two worlds, not one - the sensible world of changing physical things that we apprehend by means of our senses and the world of intelligible objects that we apprehend by means of our inte llects or minds. For him, both are real worlds, where calling them "real" means that they exist independently of our apprehending them.
Even if neither men nor other animals that have eyes or ears or other senses existed, the world of sensible thing would exist exactly as it is. So, too, for Plato, even if there were no human beings with the characteristic human ability to think of su ch objects as truth and goodness, or justice and liberty, these objects would exist - exist independently of all thinking minds. That is why in Plato's view, the idea of the good or the idea of justice has a full measure of reality.
Plato went further. More than a full measure of reality, the world of ideas had for him a superior grade of reality. The physical things that we perceive through our senses come into being and pass away and they are continually in flux, changing in o ne way or another. They have no permanence. But though we may change our minds about the ideas we think about, they themselves are not subject to change. Unlike living organisms, they are not born and do not die. Unlike stars and atoms, they do not mo ve about in space. Unlike the familiar physical objects that surround us, they do not get hot or cold, larger or smaller, and so on.
The world of changing physical things is thus for Plato a mere shadow of the much more real world of ideas. When we pass from the realm of sense experience to the realm of thought, we ascend to a higher reality, for we have turned from things that hav e no enduring existence to enduring and unchanging (Plato would say "eternal") objects of thought - i.e. ideas.
For those of us who cannot shuck off our commitment to common sense, Plato goes too far in attributing reality to ideas, and much too far in exalting their reality over the reality of sensible phenomena - the reality of the ever-changing world we exper ience through our senses. We do not hesitate to reject Plato's theory of ideas, and declare him wrong in attributing reality to ideas as well as to physical things, and a superior reality at that. For us commonsense fellows, it is the world of ideas tha t is comparatively shadowy as compared with the tangible, visible, audible world of things that press on us from all sides.
However, we, too, would be going to far if we regarded ideas as having no existence at all, or regarded them as existing only in our minds when we are thinking. That would make them entirely subjective, as subjective as the feeling of pain you experie nce when a finger is squeezed too hard, or as subjective as the toothache you have that you can tell me about but that I cannot experience because at the moment it is yours and yours alone.
Plato was right, not wrong, in holding that ideas are objects that the human mind can think about. He was right in insisting on their objectivity. This, understood in the simplest manner possible, amounts to saying that you and I can engage in conver sation about one and the same idea because it is an object that you and I are thinking about, just as you and I can engage in conversation about one and the same overcoat when you help me put it on and ask me whether it is warm enough. When you and I dis cuss truth or justice, the idea of truth or justice is before our minds, or present to our minds, just as much as the overcoat that you help me on with is handled by both of us at the same time.
If anyone has difficulty in understanding this, it is because the word "idea" has two meanings, not one - one in which it is used to refer to something that is entirely subjective and one in which it is used to refer to something that is quite objectiv e. In the first meaning, the word has been used to refer to the whole range of entities that comprise the ideational content of our consciousness. In this braid sense of the word, it covers the sensations and perceptions we have, the images we form, the memories we summon up, and the conceptions or notions that we employ in our thinking
When the word "idea" is used in this way by psychologists, all the various items referred to are certainly subjective. My sensations or perceptions are not yours; the images that occur in my dreams or the memories I dwell upon when I reminisce are min e alone; so, too, are the concepts or notions I have been at some pains to form as I study a difficult science.
To call them all "subjective" is simply to say that they are private, not public. When I speak of them as mine - my perceptions, my memory, or my concept - I am saying that the perception, memory, or concept in question belongs to me and me alone. Yo u can have no access it it, just as you cannot have access to the toothache I am suffering.
In its other meaning, the word "idea" refers to an object that two or more persons can have access to, can focus on, can think about, can discuss. While this meaning may not be as familiar, neither is it entirely strange or puzzling.
What all this comes to can be summed up by advising readers that this book about six great ideas is not concerned with psychology. It is not concerned with what goes on in people's minds when they think, or what concepts or notions they have in their minds and employ to think with. It is concerned solely with what they have before their minds when they engage in thinking - with object they are together considering and about which they and other human beings over the centries have raised questions and , in answering them, have either agreed or disagreed.
For anyone who is incurably addicted to the subjective sense in which the word "idea" is used by most people, I would be willing to drop the word entirely and substitute "object of thought" for it. But I would much prefer retaining the word and have m y readers remember that, as I am using it in a book about six great ideas, I am always writing about six great objects of thought that all of us can focus our minds on, not about the particular concepts or notions that each of us may employ in order to do that.
There would be stars and atoms in the physical cosmos with no human beings or other living organisms to perceive them. But there would be no ideas (existing formally) as objects of thought without minds to think about them. (Yet the idea of gravity a nd the abstract laws expressing the characteristics of gravity, exist fundamentally in the world of moving material things.)
7th questions