30 The Eugenics Review Mr. Brower's recent article on Eutelegenesis* and Professor Muller's book [italics]Out of the Night.[end italics][dagger] Here it must suffice to point out that unless we alter the social framework of law and ideas so as to make possible the divorce between sex and reproduction, or if you prefer it between the individual and the social sides of our sexual functions, our efforts at evolutionary improvement will remain mere tinkering, no more deserving the proud title of eugenics than does the mending of saucepans deserve to be called engineering. That consummation, you will perhaps say, is impossibly remote from our imperfect present, hardly to be affected by any of our little strivings to-day. That may be so: but I am not so sure. Let us remember that modern science is a mere three centuries old: yet is has already achieved changes in outlook that are of comparable magnitude. Biological science is only now attaining its maturity, and the social sciences are mere infants. Looked at in the long perspective of evolution, the present phase of human activity is one of transition between that of acceptance and that of control of destiny, between magic and science, between unconsciously nurtured phantasy and consciously-faced reason. It is, in the sense of the word used in physics, a critical phase: and being so it cannot be either stable or long-enduring. It is to my mind not only permissible but highly desirable to look far ahead. Otherwise we are in danger of mistaking for our eugenic ideal a mere glorification of our prejudices and our subjective wish-fulfilments. It is not eugenics but left-wing politics if we merely talk of favouring the survival and reproduction of the proletariat at the expense of the bourgeosie. It is not eugenics but right-wing politics if we merely talk of favouring the breeding of the upper classes of our present social system at the expense of the lower. It is not eugenics but nationalis and imperialist politics if we speak in such terms as subject races or miscegenation. Our conclusions in any particular case [italics]may[end italics] be on balance eugenically correct (though the correlation between broad social or ethnic divisions and genetic values can never be high), yet they will not be based primarily upon eugenic considerations, but upon social or national bias. The public-school ideal, or that of the working-class movement, or that of colonial imperialism, may be good ideals; but they are not eugenic ideals. [italics]The Danger of Man's Genetic Degeneration: Conclusion[end italics] Before concluding, I should like to draw attention to one eugenically important consequence of recent progress in pure genetics. In all organisms so far investigated, deleterious mutations far outnumber useful ones. There is an inherent tendency for the hereditary constitution to degrade itself. That man shares this tendency we can be sure, not only from analogy but on the all-too-obvious evidence provided by the high incidence in "civilized" populations of defects, both mental and physical, of genetic origin. In wild animals and plants, this tendency is either reversed or at least held in check by the operation of natural selection, which here again proves itself to be, in R. A. Fisher's words, a mechanism capable of generating high degrees of improbability. In domestic animals and plants, the same result if achieved by our artificial selection. But in civilized human communities of our present type, the elimination of defect by natural selection is largely (though of course by no means wholly) rendered inoperative by medicine, charity, and the social services; while, as we have seen, there is no selection encouraging favourable variations. The net result is that many deleterious mutations can and do survive, and the tendency to degradation of the germ-plasm can manifest itself. To-day, thanks to the last fifteen years' work in pure science, we can be sure of this alarming fact, whereas previously it was only a vague surmise.* Humanity will gradually destroy itself from within, will decay in its very core and essence, if this slow but [left side column-width hairline rule over footnotes] [footnotes]*Brewer, H., 1935. [dagger]Muller, H. J., 1935. [right side column-width hairline rule over footnote] [footnote]* Muller, H. J., 1935. [end]