A member of the Sephardic Jewish community of Amsterdam, Spinoza received a thorough education in the tradition of medieval philosophical texts as well as in the works of Descartes, Hobbes, and other writers of the period. After charges of heretical thought and practice led to his excommunication from the Jewish community in Amsterdam in 1656, he Latinized his name to Benedict. He was by trade a lens grinder, modestly rejecting offers of an academic career, but he nevertheless became celebrated in his own day and was regularly visited by other philosophers. Spinoza's system is monist, deductive, and rationalistic. Politically he posited the idea of the social contract, but unlike Hobbes he visualized a community in which human beings derive most advantage from the rational renunciation of personal desire. He rejected the concept of free will, holding human action to be motivated by one's conception of self-preservation. A powerful, or virtuous, person acts out of understanding; thus freedom consists in being guided by the law of one's own nature, and evil is the result of inadequate understanding. He saw the supreme ambition of the virtuous person as the "intellectual love of God." Spinoza shared with Descartes an intensely mathematical appreciation of the universe: truth, like geometry, follows from first principles, and is accessible to the logical mind. Unlike Descartes, however, he regarded mind and body (or ideas and the physical universe) as merely different aspects of a single substance, which he called alternately God and Nature, God being Nature in its fullness. This pantheism was considered blasphemous by the religious and political authorities of his day. Of his works, only A Treatise on Religious and Political Philosophy (1670) was published during his lifetime. His Ethics, Political Treatise, and Hebrew Grammar are included in his posthumous works (1677).