life has laws, which it is possible to ascertain; and with each bit of knowledge acquired, the environment is changed, the life becomes a new thing. consider, for example, what a different place the world became to the man who discovered that the force which laid the forest in ashes could be tamed and made to warm a cave and make wild grains nutritious! in other words, man can create life, he can make the world and himself into that which his reason decides it ought to be. the means by which he does this is the most magical of all the tools he has invented since his arboreal ancestor made the first club; the tool of experimental science—and when one considers that this weapon has been understood and deliberately employed for but two or three centuries, he realizes that we are indeed only at the beginning of human evolution.

to take command of life, to replace instincts by reasoned and deliberate acts, to make the world a conscious and ordered product—that is the task of man. sir ray lankester has set this forth with beautiful precision in his book, "the kingdom of man". we are, at this time, in an uncomfortable and dangerous transition stage, as a child playing with explosives. this child has found out how to alter his environment in many startling ways, but he does not yet know why he wishes to alter it, nor to what purpose. he finds that certain things are uncomfortable, and these he proceeds immediately to change. discovering that grain fermented dispels boredom, he creates a race of drunkards; discovering that foods can be produced in profusion, and prepared in alluring combinations, he makes himself so many diseases that it takes an encyclopedia to tell about them. discovering that captives taken in war can be made to work, he makes a procession of empires, which are eaten through with luxury and corruption, and fall into ruins again.

this is nature's way; she produces without limit, groping blindly, experimenting ceaselessly, eliminating ruthlessly. it takes a million eggs to produce one salmon; it has taken a million million men to produce one idea—algebra, or the bow and arrow, or democracy. nature's present impulse appears as a rebellion against her own methods; man, her creature, will emancipate himself from her law, will save himself from her blindness and her ruthlessness. he is "nature's insurgent son"; but, being the child of his mother, goes at the task in her old blundering way. some men are scheduled to elimination because of defective eyesight; they are furnished with glasses, and the breeding of defective eyes begins. the sickly or imbecile child would perish at once in the course of nature; it is saved in the name of charity, and a new line of degenerates is started.

what shall we do? return to the method of the spartans, exposing our sickly infants? we do not have to do anything so wasteful, because we can replace the killing of the unfit by a scientific breeding which will prevent the unfit from getting a chance at life. we can replace instinct by self-discipline. we can substitute for the regime of "nature red in tooth and claw with ravin" the regime of man the creator, knowing what he wishes to be and how to set about to be it. whether this can happen, whether the thing which we call civilization is to be the great triumph of the ages, or whether the human race is to go back into the melting pot, is a question being determined by an infinitude of contests between enlightenment and ignorance: precisely such a contest as occurs now, when you, the reader, encounter a man who has thought his way out to the light, and comes to urge you to perform the act of self-emancipation, to take up the marvellous new tools of science, and to make yourself, by means of exact knowledge, the creator of your own life and in part of the life of the race.