Nietzsche saw all this clearly as early as 1877.[20] He saw that what passed for civilization, as represented by Christianity, was making such an effort to defy and counteract the law of natural selection, and he came to the conclusion that the result would be disaster. Christianity, he said, ordered that the strong should give part of their strength to the weak, and so tended to weaken the whole race. Self-sacrifice, he said, was an open defiance of nature, and so were all the other Christian virtues, in varying degree. He proposed, then, that before it was too late, humanity should reject Christianity, as the "greatest of all imaginable corruptions," and admit freely and fully that the law of natural selection was universal and that the only way to make real progress was to conform to it.
It may be asked here how Nietzsche accounted for the fact that humanity had survived so long--for the fact that the majority of men were still physically healthy and that the race, as a whole, was still fairly vigorous. He answered this in two ways. First, he denied that the race was maintaining to the full its old vigor. "The European of the present," he said, "is far below the European of the Renaissance." It would be absurd, he pointed out, to allege that the average German of 1880 was as strong and as healthy--i.e. as well fitted to his environment--as the "blond beast" who roamed the Saxon lowlands in the days of the mammoth. It would be equally absurd to maintain that the highest product of modern civilization--the town-dweller--was as vigorous and as capable of becoming the father of healthy children as the intelligent farmer, whose life was spent in approximate accordance with all the more obvious laws of health.
Nietzsche's second answer was that humanity had escaped utter degeneration and destruction because, despite its dominance as a theory of action, few men actually practiced Christianity. It was next to impossible, he said, to find a single man who, literally and absolutely, obeyed the teachings of Christ.[21] There were plenty of men who thought they were doing so, but all of them were yielding in only a partial manner. Absolute Christianity meant absolute disregard of self. It was obvious that a man who reached this state of mind would be unable to follow any gainful occupation, and so would find it impossible to preserve his own life or the lives of his children. In brief, said Nietzsche, an actual and utter Christian would perish today just as Christ perished, and so, in his own fate, would provide a conclusive argument against Christianity.
Nietzsche pointed out further that everything which makes for the preservation of the human race is diametrically opposed to the Christian ideal. Thus Christianity becomes the foe of science. The one argues that man should sit still and let God reign; the other that man should battle against the tortures which fate inflicts upon him, and try to overcome them and grow strong. Thus all science is unchristian, because, in the last analysis, the whole purpose and effort of science is to arm man against loss of energy and death, and thus make him self-reliant and unmindful of any duty of propitiating the deity. That this antagonism between Christianity and the search, for truth really exists has been shown in a practical way time and again. Since the beginning of the Christian era the church has been the bitter and tireless enemy of all science, and this enmity has been due to the fact that every member of the priest class has realized that the more a man learned the more he came to depend upon his own efforts, and the less he was given to asking help from above. In the ages of faith men prayed to the saints when they were ill. Today they send for a doctor. In the ages of faith battles were begun with supplications, and it was often possible to witness the ridiculous spectacle of both sides praying to the same God. Today every sane person knows that the victory goes to the wisest generals and largest battalions.
Nietzsche thus showed, first, that Christianity (and all other ethical systems having self-sacrifice as their basis) tended to oppose the law of natural selection and so made the race weaker; and secondly, that the majority of men, consciously or unconsciously, were aware of this, and so made no effort to be absolute Christians. If Christianity were to become universal, he said, and every man in the world were to follow Christ's precepts to the letter in all the relations of daily life, the race would die out in a generation. This being true--and it may be observed in passing that no one has ever successfully controverted it--there follows the converse: that the human race had best abandon the idea of self-sacrifice altogether and submit itself to the law of natural selection. If this is done, says Nietzsche, the result will be a race of supermen--of proud, strong dionysians--of men who will say "yes" to the world and will be ideally capable of meeting the conditions under which life must exist on earth.