In the teachings of Mencius (B.C. 372-289) we see a distinct advance on the doctrines of Confucius. He was a man of a far more practical frame of mind than his great predecessor, and possessed the courage necessary to speak plainly in the presence of kings and rulers. His knowledge of political economy was considerable, and he brought to the test of experience many of the opinions and doctrines which Confucius was willing to express only in the abstract. Filial piety was his constant theme. "The richest fruit of benevolence is this," he said,--"the service of one's parents. The richest fruit of righteousness is this,--the obeying of one's elder brothers. The richest fruit of wisdom is this,--the knowing of these two things, and not departing from them." These Five Classics and Four Books may be said to be the foundations on which all Chinese literature has been based. The period when Confucius and Mencius taught and wrote was one of great mental activity all over the world. While the wise men of China were proclaiming their system of philosophy, the Seven Sages of Greece were pouring out words of wisdom in the schools at Athens, and the sound of the voice of Buddha (died 480 B.C.) had hardly ceased to be heard under the bodhi tree in Central India. From such beginnings arose the literatures which have since added fame and splendor to the three countries in Asia and Europe. In China the impetus given by these pioneers of learning was at once felt, and called into existence a succession of brilliant writers who were as distinguished for the boldness of their views as for the freedom with which they gave them utterance. The main subject discussed by these men was the principle underlying the Confucian system; namely, that man's nature is in its origin perfectly good, and that so long as each one remains uncontaminated by the world and the things of the world, the path of virtue is to him the path of least resistance. While therefore a man is able to remain unenticed by the temptations which necessarily surround him, he advances in spotless purity towards perfection, until virtue becomes in him so confirmed a habit that neither the stings of conscience nor the exertion of intellectual effort is required to maintain him in his position of perfect goodness and of perfect peace.