_In general, those ideas which are still almost universally accepted in regard to man's nature, his proper conduct, and his relations to God and his fellows are far more ancient and far less critical than those which have to do with the movement of the stars, the stratification of the rocks and the life of plants and animals_. Nothing is more essential in our attempt to escape from the bondage of consecrated ideas than to get a vivid notion of human achievement in its proper historical perspective. In order to do this let us imagine the whole gradual and laborious attainments of mankind compressed into the compass of a single lifetime. Let us assume that a single generation of men have in fifty years managed to accumulate all that now passes for civilization. They would have to start, as all individuals do, absolutely uncivilized, and their task would be to recapitulate what has occupied the race for, let us guess, at least five hundred thousand years. Each year in the life of a generation would therefore correspond to ten thousand years in the progress of the race. On this scale it would require forty-nine years to reach a point of intelligence which would enable our self-taught generation to give up their ancient and inveterate habits of wandering hunters and settle down here and there to till the ground, harvest their crops, domesticate animals, and weave their rough garments. Six months later, or half through the fiftieth year, some of them, in a particularly favorable situation, would have invented writing and thus established a new and wonderful means of spreading and perpetuating civilization. Three months later another group would have carried literature, art, and philosophy to a high degree of refinement and set standards for the succeeding weeks. For two months our generation would have been living under the blessings of Christianity; the printing press would be but a fortnight old and they would not have had the steam engine for quite a week. For two or three days they would have been hastening about the globe in steamships and railroad trains, and only yesterday would they have come upon the magical possibilities of electricity. Within the last few hours they would have learned to sail in the air and beneath the waters, and have forthwith applied their newest discoveries to the prosecution of a magnificent war on the scale befitting their high ideals and new resources. This is not so strange, for only a week ago they were burning and burying alive those who differed from the ruling party in regard to salvation, eviscerating in public those who had new ideas of government, and hanging old women who were accused of traffic with the devil. All of them had been no better than vagrant savages a year before. Their fuller knowledge was altogether too recent to have gone very deep, and they had many institutions and many leaders dedicated to the perpetuation of outworn notions which would otherwise have disappeared.