If the human organism is to develop normally and healthfully it is essential that no portion of the human body should be neglected, and that no natural impulse should be denied its normal satisfaction. Every organ should perform the functions which it has been destined by nature to perform, unless the whole organism is to suffer. The laws of the physical development of man must be studied and observed as well as the laws of mental development. The mental activity of a human being depends upon the physiological condition of his organs. Physical and mental vigor are closely linked. An injury to one has a detrimental effect upon the other. The so-called animal instincts are not inferior to mental requirements. Both are products of the same organism and are mutually interdependent. This applies to both man and woman. Hence it follows that knowledge of the nature of the sexual organs is as necessary as that of all other organs, and that the same attention should be bestowed upon their care. We ought to know that organs and impulses implanted in every human being constitute a very important part of our existence, that they as a matter of fact ~predominate~ during certain periods of life, and that therefore they must not be objects of secrecy, false shame and complete ignorance. It follows furthermore that among both men and women knowledge of the physiology and anatomy of the various organs and their functions should be as widely diffused as any other branch of human knowledge. Endowed with an exact knowledge of his physical nature, man would take a different view of many circumstances. This knowledge would lead to the removal of many evils that society at present passes by silently, in solemn awe, but that nevertheless claim consideration in almost every family. In regard to all other matters knowledge is considered ~a~ virtue; it is regarded as the loftiest, most desirable human aim. But we decry knowledge pertaining to ~those~ matters that are most closely linked with our own “ego” and are at the bottom of all social development. Kant says: “Man and woman together form the full and complete human being; one sex supplements the other.” Schopenhauer says: “The sexual impulse is the most complete expression of the will to live, it is the concentration of will”; and long before these Buddha thus expressed himself: “The sexual impulse is sharper than the prod by means of which wild elephants are tamed; it is hotter than flames; it is like an arrow driven into the soul of man.”