Between 334 and his death Alexander conquered most of the world known to antiquity. Alexander, who was a pupil of Aristotle, inherited a plan to invade Persia from his father Philip 11; having secured his position in Macedon and Greece, he put this plan into action. In 333 he defeated the Persian king Darius III at Issus; in 332 he reduced Tyre in his greatest victory. Alexander then proceeded to conquer Egypt and Babylon (331). Moving on to Media and then east into central Asia, he finally embarked on the Indian expedition (327- 325). He crossed the River Indus and conquered the Punjab. Forced to turn back by his reluctant army, he died at Babylon shortly after the marathon return journey. In the administration of his empire Alexander adopted a novel policy of appointing subject races to posts of responsibility, which some historians have called idealism and others, opportunism. His outstanding gifts as a general, however, are indisputable.