Baruch de Spinoza and later Benedict de Spinoza (November 24, 1632 – February 21, 1677) was a Dutch philosopher. Revealing considerable scientific aptitude, the breadth and importance of Spinoza's work was not fully realized until years after his death. By laying the groundwork for the 18th century Enlightenment and modern biblical criticism, he came to be considered one of the great rationalists of the 17th-century philosophy. And his magnum opus, the posthumous Ethics, in which he opposed Descartes' mind–body dualism, has also earned him recognition as one of Western philosophy's most important contributors. Philosopher Georg Wilhelm Friedrich Hegel said of all contemporary philosophers, "You are either a Spinozist or not a philosopher at all."
Spinoza was raised in the Dutch Jewish community. In time he developed highly controversial ideas regarding the authenticity of the Hebrew Bible and the nature of the Divine. The Jewish religious authorities issued a cherem (a kind of excommunication) against him, effectively dismissing him from Jewish society at age 23. His books were also later put on the Catholic Church's Index of Forbidden Books.