This distrust of the unknown, this fear of doing something unusual, is probably at the bottom of many ideas and institutions that are commonly credited to other motives. For example, monogamy. The orthodox explanation of monogamy is that it is a manifestation of the desire to have and to hold property—that the husband defends his solitary right to his wife, even at the cost of his own freedom, because she is the pearl among his chattels. But Dr. Parsons argues, and with a good deal of plausibility, that the real moving force, both in the husband and the wife, may be merely the force of habit, the antipathy to experiment and innovation. It is easier and safer to stick to the one wife than to risk adventures with another wife—and the immense social pressure that I have just described is all on the side of sticking. Moreover, the indulgence of a habit automatically strengthens its bonds. What we have done once or thought once, we are more apt than we were before to do and think again. Or, as the late Prof. William James put it, “the selection of a particular hole to live in, of a particular mate, ... a particular anything, in short, out of a possible multitude ... carries with it an insensibility to _other_ opportunities and occasions—an insensibility which can only be described physiologically as an inhibition of new impulses by the habit of old ones already formed. The possession of homes and wives of our own makes us strangely insensible to the charms of other people.... The original impulse which got us homes, wives, ... seems to exhaust itself in its first achievements and to leave no surplus energy for reacting on new cases.” Thus the benedict looks no more on women (at least for a while), and the post-honeymoon bride, as the late David Graham Phillips once told us, neglects the bedizenments which got her a man.