So far we have been dealing with fundamental laws and tendencies, which were established long before Man appeared on the earth, although Man has often illustrated, and still illustrates, their inevitable character. We have not been brought in contact with the influence of conscious design and deliberate intention. At this point we reach a totally new aspect of reproduction. II. THE ORIGIN AND RESULTS OF BIRTH CONTROL In tracing the course of reproduction we have so far been concerned with what are commonly considered the blind operations of Nature in the absence of conscious and deliberate volition. We have seen that while at the outset Nature seems to have impressed an immense reproductive impetus on her creatures, all her energy since has been directed to the imposition of preventive checks on that reproductive impetus. The end attained by these checks has been an extreme diminution in the number of offspring, a prolongation of the time devoted to the breeding and care of each new member of the family, in harmony with its greatly prolonged life, a spacing out of the intervals between the offspring, and, as a result, a vastly greater development of each individual and an ever better equipment for the task of living. All this was slowly attained automatically, without any conscious volition on the part of the individuals, even when they were human beings, who were the agents. Now occurred a change which we may regard as, in some respects, the most momentous sudden advance in the whole history of reproduction: the process of reproductive progress became conscious and deliberately volitional. We often fancy that when natural progress becomes manifested in the mind and will of man it is somehow unnatural. It is one of the wisest of Shakespeare's utterances in one of the most mature of his plays that "Nature is made better by no mean But Nature makes that mean ... This is an art Which does mend Nature, change it rather, but The art itself is Nature." Birth control, when it ceases to be automatic and becomes conscious, is an art. But it is an art directed precisely to the attainment of ends which Nature has been struggling after for millions of years, and, being consciously and deliberately an art, it is enabled to avoid many of the pitfalls which the unconscious method falls into. It is an art, but "The art itself is Nature."