The facts stated in the foregoing chapters are familiar and undeniable, the argument seems clear; yet the mind reacts violently from the conclusions it is forced to admit, and tries to find relief in the commonplace conditions of every-day life. From this looming phantom of the over-sexed female of genus homo we fly back in satisfaction to familiar acquaintances and relatives,—to Mrs. John Smith and Miss Imogene Jones, to mothers and sisters and daughters and sweethearts and wives. We feel that such a dreadful state of things cannot be true, or we should surely have noticed it. We may even perform that acrobatic feat so easy to most minds,—admit that the statement may be theoretically true, but practically false! Two simple laws of brain action are responsible for the difficulty of convincing the human race of any large general truths concerning itself. One is common to all brains, to all nerve sensations indeed, and is cheerfully admitted to have nothing to do with the sexuo-economic relation. It is this simple fact, in popular phrase,—that what we are used to we do not notice. This rests on the law of adaptation, the steady, ceaseless pressure that tends to fit the organism to the environment. A nerve touched for the first time with a certain impression feels this first impression far more than the hundredth or thousandth, though the thousandth be far more violent than the first. If an impression be constant and regular, we become utterly insensitive to it, and only respond under some special condition, as the ticking of a clock, the noise of running water or waves on the beach, even the clatter of railroad trains, grows imperceptible to those who hear it constantly. It is perfectly possible for an individual to become accustomed to the most disadvantageous conditions, and fail to notice them. It is equally possible for a race, a nation, a class, to become accustomed to most disadvantageous conditions, and fail to notice them. Take, as an individual instance, the wearing of corsets by women. Put a corset, even a loose one, on a vigorous man or woman who never wore one, and there is intense discomfort, and a vivid consciousness thereof. The healthy muscles of the trunk resent the pressure, the action of the whole body is checked in the middle, the stomach is choked, the process of digestion interfered with; and the victim says, “How can you bear such a thing?”