Of all the problems which the alert and curious mind of modern man is considering, none occupies him more than that of the relations of the sexes. This is natural. It touches us all and we have made rather a mess of it! We want to know why, and we want to do better. We resent being the sport of circumstance and perhaps we are beginning to understand that this instinct of sex which has been so great a cause of suffering and shame and has been treated as a subject fit only for furtive whispers or silly jokes, is in fact one of the greatest powers in human nature, and that its misuse is indeed "the expense of spirit in a waste of shame."It is not the abnormal or the bizarre that interests most of us to-day. It is not into the by-ways of vice that we seek to penetrate. It is the normal exercise of a normal instinct by normal people that interests us: and it is of this that I have tried to write and speak. The curiosities of depravity are for the physician and the psychologist to discuss and cure. Ordinary men and women want first to know how to live ordinary human lives on a higher level and after a nobler pattern than before. They want, I think, - and I want, - to grow up, but to grow rightly, beautifully, humanely.And I believe the first essential is to realize that the sex-problem, as it is called, is the problem of something noble, not something base. It is not a "disagreeable duty" to know our own natures and understand our own instincts: it is a joy. The sex-instinct is not "the Fall of Man"; neither is it an instance of divine wisdom on which moralists could, if they had only been consulted in time, greatly have improved. It is a thing noble in essence. It is the development of the higher, not the lower, creation. It is the asexual which is the lower, and the sexually differentiated which is the higher organism.