INTRODUCTION
some respects the most striking result, of certain laws that hold throughout the animal and plant worlds. The more extended and more profound study of living things has revealed the manifold forms of animal life as one great series, in which the more complex are traceable by descent—or rather by ascent—from primitive simpler ancestral forms; and man is seen to have had his origin in a prehuman and subhuman animal stock, a stock which itself had in its time slowly attained to qualities and powers that made possible the attainment of man’s own present estate. We can recognize in that estate a nature that relates us to much we might fain discard, and yet a nature that has been a passport for our further travel upward and has qualified us to achieve not only what man in the aggregate has achieved but what individual man at his best stands for. Thus, so far as face images forth mind, the reflection that from some simian grimace there has been evolved with the progress of time the smile of Mona Lisa is an exhortation to fortify man in his effort to gratify his yearning for higher things and for a yet more highly perfected future.
The creation of man perceived as a gradual and still operative evolutionary process, which, besides bringing him into existence is still moulding him and will not leave him where he is and as he is, bears broadly and profoundly on the interpretation of all human activities. This perception affords him new guidance in tracing to their origins his instincts, his emotions, his interests, and his reasoning power. In the light of this perception civilization and the history of civilization acquire fresh meanings; human society—its customs, its duties, and its growth—stand visible from a new angle and in truer perspective. There is incumbent, therefore, on every thinking man and woman, faced with the responsibilities of citizenship, an obligation to inform himself or
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