(Attempts to show what we know about life; to set the bounds of real truth as distinguished from phrases and self-deception.) If I could, I would begin this book by telling you what Life is. But unfortunately I do not know what Life is. The only consolation I can find is in the fact that nobody else knows either. We ask the churches, and they tell us that male and female created He them, and put them in the Garden of Eden, and they would have been happy had not Satan tempted them. But then you ask, who made Satan, and the explanation grows vague. You ask, if God made Satan, and knew what Satan was going to do, is it not the same as if God did it himself? So this explanation of the origin of evil gets you no further than the Hindoo picture of the world resting on the back of a tortoise, and the tortoise on the head of a snake--and nothing said as to what the snake rests on. Let us go to the scientist. I know a certain physiologist, perhaps the greatest in the world, and his eager face rises before me, and I hear his quick, impetuous voice declaring that he knows what Life is; he has told it in several big volumes, and all I have to do is to read them. Life is a tropism, caused by the presence of certain combinations of chemicals; my friend knows this, because he has produced the thing in his test-tubes. He is an exponent of a way of thought called Monism, which finds the ultimate source of being in forms of energy manifesting themselves as matter; he shows how all living things arise from that and sink back into it. But question this scientist more closely. What is this "matter" that you are so sure of? How do you know it? Obviously, through sensations. You never know matter itself, you only know its effects upon you, and you assume that the matter must be there to cause the sensation. In other words, "matter," which seems so real, turns out to be merely "a permanent possibility of sensation." And suppose there were to be sensations, caused, for example, by a sportive demon who liked to make fun of eminent physiologists--then there might be the appearance of matter and nothing else; in other words, there might be mind, and various states of mind. So we discover that the materialist, in the philosophic sense, is making just as large an act of faith, is pronouncing just as bold a dogma as any priest of any religion.