If we are responsible for our thoughts, we ought not only to know how they are formed, but we ought to form them. If we are the masters of our own minds, we ought to be able to tell what we are going to think at any future time. Evidently, the food of thought--its very warp and woof--is furnished through the medium of the senses. If we open our eyes, we cannot help seeing. If we do not stop our ears, we cannot help hearing. If anything touches us, we feel it. The heart beats in spite of us. The lungs supply themselves with air without our knowledge. The blood pursues its old accustomed rounds, and all our senses act without our leave. As the heart beats, so the brain thinks. The will is not its king. As the blood flows, as the lungs expand, as the eyes see, as the ears hear, as the flesh is sensitive to touch, so the brain thinks. I had a dream, in which I debated a question with a friend. I thought to myself: "This is a dream, and yet I can not tell what my opponent is going to say. Yet, if it is a dream, I am doing the thinking for both sides, and therefore ought to know in advance what my friend will urge." But, in a dream, there is some one who seems to talk to us. Our own brain tells us news, and presents an unexpected thought. Is it not possible that each brain is a field where all the senses sow the seeds of thought? Some of these fields are mostly barren, poor, and hard, producing only worthless weeds; and some grow sturdy oaks and stately palms; and some are like the tropic world, where plants and trees and vines seem royal children of the soil and sun. Nothing seems more certain than that the capacity of a human being depends, other things being equal, upon the amount, form, and quality of his brain. We also know that health, disposition, temperament, occupation, food, surroundings, ancestors, quality, form, and texture of the brain, determine what we call character. Man is, collectively and individually, what his surroundings have made him. Nations differ from each other as greatly as individuals in the same nation. Nations depend upon soil, climate, geographical position, and countless other facts. Shakespeare would have been impossible without the climate of England. There is a direct relation between Hamlet and the Gulf Stream. Dr. Draper has shown that the great desert of Sahara made negroes possible in Africa. If the Caribbean Sea had been a desert, negroes might have been produced in America. Are the effects of climate upon man necessary effects? Is it possible for man to escape them? Is he responsible for what he does as a consequence of his surroundings? Is the mind dependent upon causes? Does it act without cause? Is every thought a necessity? Can man choose without reference to any quality in the thing chosen?