"Choose well, your choice is brief and yet endless," says Carlyle. You are driven in your choice by two facts--first, that you have to choose, regardless of whether you want to or not; and second, that upon your choice depend infinite possibilities of happiness or of misery. The interdependence of life is such that you are choosing not merely for the present, but for the future; you are choosing for your posterity forever, and to some extent you are choosing for all mankind. Matthew Arnold has said that "Conduct is three-fourths of life"; but I, for my part, have never been able to see where he got his figures. It seems to me that conduct is practically everything in life that really counts. Conduct is not merely marriage and birth and premature death; it is not merely eating and drinking and sleeping: it is thinking and aspiring; it is religion and science, music and literature and art. It is not yet the lightning and the cyclone, but with the spread of knowledge it is coming to be these things, and I suspect that some day it may be even the comet and the rising of the sun. We are now going to apply our reason to this enormous problem of human conduct; we are going to ask ourselves the question: What kind of life do we want? What kind of life are we going to make? What are the standards by which we may know excellence in life, and distinguish it from failure and waste and blunder in life? Obviously, when we have done this, we shall have solved the moral problem; all we shall have to say is, act so that your actions help to bring the desirable things into being, and do not act so as to hinder or weaken them. We shall not be able to go to nature to settle this question for us. This is our problem, not nature's. But we shall find, as usual, that we can pick up precious hints from her; we shall be wise to study her ways, and learn from her successes and her failures. We are proud of her latest product, ourselves. Let us see how she made us; what were the stages on the way to man? First in the scale of evolution, it appears, came inert matter. We call it inert, because it looks that way, though we know, of course, that it consists of infinite numbers of molecules vibrating with speed which we can measure even though we cannot imagine it. This "matter" is enormously fascinating, and a wise man will hesitate to speak patronizingly about it. Nevertheless, considering matter apart from the mind which studies it, we decide that it represents a low stage of being. We speak contemptuously of stones and clods and lumps of clay. We award more respect to things like mountains and tempest-tossed oceans, because they are big; in the early days of our race we used to worship these things, but now we think of them merely as the raw material of life, and we should not be in the least interested in becoming a mountain or an ocean.