But here there arises a new difficulty in regard to truth. If the usefulness of the intellect consists in the active production of an illusion, can we say that the intellect leads us to truth? Is it not only if we can turn away from the intellect and obtain a non-intellectual intuition that we can know truth? {67} CHAPTER VII ILLUSION The doctrine that the world that appears is essentially unlike the world that is is neither new nor peculiar to any particular theory of philosophy. It has received a new interest and a new interpretation lately in the theory that we are now considering, that the clue to the appearance of the world to us is to be found in the conception of the nature of the utility of the intellect and in the mode of its activity. The idea that we are perhaps disqualified by our very nature itself from beholding reality and knowing truth is illustrated in the well-known allegory in the _Republic_ of Plato: "And now let me show in a figure how far our nature is enlightened or unenlightened. Behold! human beings living in an underground den, which has a mouth open towards the light and reaching all along the den; here they have been from their childhood, and have their legs and necks chained so that they cannot move and can only see before them, being prevented by the chains from turning round their heads. Above and behind them a fire is blazing at a distance, and between the fire and the prisoners there is a raised way; and you will see, if you look, a low wall built along the way, like the screen which marionette players have in front of them, over which they show the puppets. And men are passing along the wall carrying all sorts of vessels, and statues, and figures of animals made of wood and stone and various materials, which appear over the wall.... "They are strange prisoners, like ourselves, and they see only their own shadows or the shadows of one another which the fire throws on the opposite wall of the cave. And so also of the objects carried and of the passers-by; to the prisoners the truth would be literally nothing but the shadows of the images. {68} "And now look again, and see what will naturally follow if the prisoners are released and disabused of their error. At first, when any of them, is liberated and compelled suddenly to stand up and turn his neck round and walk and look towards the light, he will suffer sharp pains; the glare will distress him, and he will be unable to see the realities of which in his former state he had seen the shadows. And then conceive someone saying to him that what he saw before was an illusion, but that now, when he is approaching nearer to being, and his eye is turned towards more real existence, he has a clearer vision, and what will be his reply? Will he not fancy that the shadows which he formerly saw are truer than the objects which are now shown to him?...