3. But, beside this passion for the ideal, Plato was intensely interested in our knowledge of the actual world of appearances around us. And one of the prime questions with which he was then concerned was the question, what we mean when we talk about the nature or character of the things we see, a plant, say, or an animal, or a man. We must mean something definite, otherwise we could not recognize, for example, that a plant _is_ a plant through all its varieties and all the different stages of its growth. Plato's answer was, that in all natural things there is a definite principle that copies, as it were, a definite Type or Form, and this Type he calls an Idea. Thus in some sense it is this Type, this Idea, this Form, that brings the particular thing into being. 4. But it was not enough for Plato to say that every natural thing had in some sense a certain type for its basis, unless he could believe that this type was good, and that all the types were harmonious with each other. He could only be satisfied with the world, in short, if he could feel that it came about through a movement towards perfection. He makes his Socrates say that in asking about 'the causes of things, what it is that makes each thing come into being', it was not enough for him if he could only see that the thing was there because something had put it there: he also wanted to see that it was good for it to be there. Socrates tells us that what he needed he thought he had found in a book by Anaxagoras, which announced 'that Mind was the disposer and cause of all' because, 'I said to myself, If this be so--if Mind is the orderer, it will have all in order, and put every single thing in the place that is best for it'.[8] It is the same feeling as that which underlies the words of Genesis about the Creation, 'And God saw that it was good'. And there is no doubt that such a view of the world would be supremely satisfying if we could count it true. There may be considerable intellectual satisfaction, no doubt, in merely solving a puzzle as to how things come about, but it is as nothing compared to the joy there would be in contemplating their goodness. 5. But is it true? Can we possibly say so in view of the hideous imperfection round us? The writers of Genesis spoke of a Fall. Plato, in his own way, speaks of a Fall himself. He never gives up the belief in an Absolute Perfection, a system of Perfect Types somehow--he does not say exactly how--influencing the structure of things in this world. But he holds that on earth this perfection is always thwarted by a medium which prevents its full manifestation. This medium is the medium of Space and Time, and therefore the medium of history--and therefore history is always and inevitably a record of failure. 'While we are in the body,' Plato writes, 'and while the soul is contaminated with its evils, our desire will never be thoroughly satisfied.'[9] 'The body is a tomb,' he writes elsewhere, quoting a current phrase.