the increase [of surviving children] would be obtained. Is it worth while to dilute our increase of population by ten per cent. more of the most inferior kind? Will England be stronger for having one-thirtieth more, and that of the worst stock, added to the population every year? This movement is doing away with one of the few remains of natural weeding out of the unfit that our civilisation has left to us. And it will certainly cause more misery than happiness in the course of a century.” Here, plainly, is a serious argument. We are bound to sympathise with its underlying assumption, viz., that not all babies are such as we can desire to carry on the race. Still more must we sympathise with any author whatever who has imagination and foresight enough to write anywhere, on any subject, wrongly or rightly, such a sentence as “and it will certainly cause more misery than happiness in the course of a century.” We need more such authors. But without going into the whole argument here--as, for instance, regarding the singular use of the word “natural”--I do most entirely deny the right of the eugenic idea to any voice or place as to the fate of children _once they have come into being_. Another writer, arguing on the same lines, says _à propos_ of the abolition of infant mortality: “This last change which, as the Huddersfield experiment shows, is easy of accomplishment, is likely to be completely effected in the next few years, and we shall then have abolished the one factor which in any important degree at present tends to redress the balance between the rates of reproduction of the superior and the inferior classes.” These are the words of Dr. W. McDougall, the distinguished psychologist. Dr. McDougall has subsequently shown that he repudiates the apparent deduction from them, and entirely approves of the present campaign of mercy to childhood. Nevertheless, these arguments, plainly derived from the principle of natural selection, do express a most important truth--viz., that indiscriminate survival must lead to racial decadence, whether in man, microbe or moss. I submit that the difficulty can be solved only by the eugenic principle. The fittest must become parents, and the unfit[2] must not; then kill the unfit, says Nature. And this indeed, in all living species other than man, is what Nature does. But “thou shalt not kill,” says the moral law--not even the unfit. As the foregoing will have shown, some thinkers to-day propose to avail themselves in this dilemma of the “New Decalogue”:-- “Thou shalt not kill but need'st not strive Officiously to keep alive.”