Baruch Spinoza was a Jewish Dutch philosopher who is considered one of the great rationalists of 17th century philosophy.
Spinoza was born in Amsterdam in 1632, into a family of Jewish emigrants fleeing persecution in Portugal. He was trained in Talmudic scholarship, but his views soon took unconventional directions which the Jewish community - fearing renewed persecution on charges of atheism - tried to discourage. Spinoza was offered 1000 florins to keep quiet about his views, but refused. At the age of 24, he was summoned before a rabbinical court, and solemnly excommunicated.
Spinoza refused all rewards and honours, and gave away to his sister his share of his father's inheritance - keeping only a bedstead for himself. He earned his living as a humble lens-grinder. He died [at the Hague] in February 1677 of consumption, probably aggravated by fine glass dust inhaled at his workbench.
His philosophy is summarized in the Ethics, a very abstract work, which openly expresses none of the love of nature that might be expected from someone who identified God with nature. And Spinoza's starting point is not nature or the cosmos, but a purely theoretical definition of God. The work then proceeds to prove its conclusions by a method modeled on geometry, through rigorous definitions, axioms, propositions and corollaries. No doubt in this way Spinoza hoped to build his philosophy on the solidest rock, but the method, as well as some of the arguments and definitions, are often unconvincing.
Spinoza believed that everything that exists is God. However, he did not hold the converse view that God is no more than the sum of what exists. God had infinite qualities, of which we can perceive only two, thought and extension. Hence God must also exist in dimensions far beyond those of the visible world.
Significantly, Spinoza titled his chief work The Ethics. He derived an ethic by deduction from fundamental principles, and so his ethics were closely linked to his view of "God or nature" as everything. The highest good, he asserted, was knowledge of God, which was capable of bringing freedom from tyranny by the passions, freedom from fear, resignation to destiny, and true blessedness.
At first Spinoza was reviled as an atheist - and certainly, his God is not the conventional Judo-Christian God. The philosophers of the enlightenment ridiculed his methods - not without some grounds. The romantics, attracted by his identification of God with Nature, rescued him from oblivion.
Sources: Scientific Pantheism