The third fact which challenged the educator was sociological; it was the existence of slavery. This institution, which in the end was one of the causes of the breakdown of ancient civilization, seemed to be perfectly natural to the philosopher. Aristotle thinks that some people are slavish by nature. He has no thought of educating such persons, though they may be trained to perform their tasks well. All should be so trained that they may live happily and well in the stations in life where they are. As most mechanical labor was performed by slaves, and by hirelings whose social status was not very different from that of the slave, the Greeks candidly despised mechanic arts. Knowledge of them was thought to be a slavish kind of skill. Aristotle likewise looked down upon trade and commerce as debasing the mind, just as hard labor was thought to demean the body. The free man must be so trained that his privileges, his leisure and authority over others would make for general human happiness. This education of the free man was called “Liberal Education.” It was the education of a leisure class. It was a training for leadership and responsibility: not a mere initiation into the idealogy of an exploiting class, together with the passwords current in exclusive circles. Neither did it mean--at least for the ancient Greek--the accumulation of dead and inconsequential knowledge the only purpose of which was a pedantic display of erudition. In ages that followed, the study of the classics tended to become something of this sort. But this tendency marked a decline, a loss of the spirit of liberal education as it had once existed. Athenian education, in spite of the institution of slavery, developed men of wisdom and nobility of spirit and civilization of interest in such numbers that ancient Greece became the pioneer of western civilization and has remained the inspiration and guide to men in most of their efforts to attain a life of reason and beauty.