Thus the answer to our first question, whether the theory of Ideas explains the world of things, must be {240} answered in the negative. Let us pass on to the second test. Is the principle of Ideas a self-explanatory principle? Such a principle must be understood purely out of itself. It must not be a principle, like that of the materialist, which merely reduces the whole universe to an ultimate mysterious fact. For even if it be shown that the reason of everything is matter, it is still open to us to ask what the reason of matter is. We cannot see any reason why matter should exist. It is a mere fact, which dogmatically forces itself upon our consciousness without giving any reason for itself. Our principle must be such that we cannot ask a further reason of it. It must be its own reason, and so in itself satisfy the demand for a final explanation. Now there is only one such principle in the world, namely, reason itself. You can ask the reason of everything else in the world. You can ask the reason of the sun, the moon, stars, the soul, God, or the devil. But you cannot ask the reason of reason, because reason is its own reason. Let us put the same thought in another way. When we demand the explanation of anything, what do we mean by explanation? What is it we want? Do we not mean that the thing appears to us irrational, and we want it shown that it is rational? When this is done, we say it is explained. Think, for example, of what is called the problem of evil. People often talk of it as the problem of the "origin of evil," as if what we want to know is, how evil began. But even if we knew this, it would not explain anything. Suppose that evil began because someone ate an apple. Does this make the matter any clearer? Do we feel that all our difficulties about the existence of evil are solved? No. This is {241} not what we want to know. The difficulty is that evil appears to us something irrational. The problem can only be solved by showing us that somehow, in spite of appearances, it is rational that evil should exist. Show us this, and evil is explained. Explanation of a thing, then, means showing that the thing is rational. Now we can ask that everything else in the world should be shown to be rational. But we cannot demand that the philosopher shall show that reason is rational. This is absurd. Reason is what is already absolutely rational. It is what explains itself. It is its own reason. It is a self-explanatory principle. This, then, must be the principle of which we are in search. The Absolute, we said, must be a self-explanatory principle, and there is only one such, namely, reason. The Absolute, therefore, is reason.