Baruch Spinoza

Baruch Spinoza was a Dutch philosopher of Portuguese Jewish origin, one of the most radical thinkers of the seventeenth century. Expelled from Amsterdam's Jewish community as a young man, he went on to argue that God and nature are one and the same, that everything happens by necessity, and that freedom comes from understanding rather than from free will. His defence of free thought and his critical reading of the Bible made him notorious in his lifetime and a major influence on the Enlightenment.

Spinoza was born in Amsterdam on 24 November 1632, in the Dutch Republic. His family were Sephardic Jews whose ancestors had been forced to convert to Christianity in Portugal and who had fled to the Netherlands, where they could openly return to Judaism. His father, Michael, was a merchant who imported dried fruit and other goods. Baruch, whose name means "blessed", was known in Portuguese as Bento and later signed his works with its Latin form, Benedictus.

He studied at the community's Talmud Torah school, learning Hebrew and the Bible and Jewish commentators, among them Maimonides. He did not go on to advanced rabbinical training. After his father died in 1654 he ran the family business with his brother, but it was burdened with debts. In these years he learned Latin, probably from the former Jesuit and freethinker Franciscus van den Enden, and began reading René Descartes and other modern authors.

On 27 July 1656 the leaders of Amsterdam's Portuguese Jewish congregation issued a herem, a ban of expulsion, against Spinoza. The document is unusually harsh, cursing him and forbidding anyone to speak with him, but it does not state precisely what he had done, referring only to "abominable heresies" and "monstrous deeds". From later sources it seems he was denying that the soul is immortal, that the Law of Moses came from God, and that God is anything more than nature in a philosophical sense. Spinoza never sought readmission and did not convert to Christianity, living instead among liberal Protestant friends, especially members of tolerant groups such as the Collegiants.

Spinoza earned part of his living by grinding lenses for telescopes and microscopes, work for which he gained a good reputation among scientists such as Christiaan Huygens. He also received small pensions from friends. Around 1661 he moved to Rijnsburg, near Leiden, then in 1663 to Voorburg, and about 1670 to The Hague, where he lived modestly in rented rooms.

The only book published under his own name in his lifetime was an exposition of Descartes's Principles of Philosophy (1663). His Theological-Political Treatise appeared anonymously in 1670 with a false place of publication, and was soon banned. In 1672, when a mob in The Hague lynched the statesmen Johan and Cornelis de Witt, who had led the republic, Spinoza was reportedly restrained by his landlord from going out to post a placard denouncing the killers as the worst of barbarians. In 1673 he turned down a professorship at the University of Heidelberg, fearing it would limit his freedom to philosophise. In 1676 the young Gottfried Wilhelm Leibniz visited him and discussed his ideas.

Spinoza's masterpiece, the Ethics, is written in the form of a geometry book, with definitions, axioms, propositions and proofs, in imitation of Euclid. It argues that there can be only one substance, existing necessarily and infinite in every respect. This substance is God, which Spinoza also calls nature, in his phrase Deus sive Natura, "God or nature". Thought and extension, which Descartes had treated as separate substances, are for Spinoza two of the infinitely many attributes of this single reality. Individual things, including human beings, are modes, or ways in which God exists.

This God is not a person who plans, judges or answers prayers. Everything follows from the divine nature with the same necessity as the properties of a triangle follow from its definition, so there are no miracles and no purposes built into nature. Mind and body are one and the same thing seen under two attributes, which removes the Cartesian problem of how they interact. Whether this view should be called pantheism, or atheism, or a new kind of religion, was disputed by his contemporaries and is still debated.

Because human beings are part of nature, Spinoza argued, their emotions can be studied as precisely as lines and planes. Each thing strives to persevere in its own being. We are in bondage when we are driven by passions caused by external things that we do not understand, such as fear, hatred and envy. We become free, in the only sense possible, when we understand the causes of our feelings and act from our own nature guided by reason. The highest happiness is the intellectual love of God, a calm understanding of our place in the necessary order of things.

In the Theological-Political Treatise, Spinoza read the Bible as a historical document written by many human authors, arguing for example that Moses could not have written all of the first five books. He held that scripture teaches obedience and charity, not philosophical truth, and that the state should therefore allow full freedom of thought and speech, which he considered necessary for peace and for true piety. Like Thomas Hobbes, he based political power on the natural strength and interests of individuals, but he concluded that democracy is the most natural and stable form of government. His later Political Treatise was left unfinished.

Spinoza died in The Hague on 21 February 1677, aged 44, of a lung disease, probably made worse by the glass dust from his work. His friends published the Ethics and his other unpublished writings later that year in his Opera Posthuma, without his name on the title page, and these were quickly banned as well.

For a century "Spinozist" was a charge of atheism, but his ideas circulated widely among radical thinkers of the Age of Enlightenment. In the 1780s a controversy over whether the German writer Lessing had been a Spinozist revived interest in him, and Goethe, Hegel and the Romantics admired him. Albert Einstein said he believed in Spinoza's God. Historians now count him among the great system-builders of early modern philosophy, and as an early advocate of secular democracy and of the historical study of the Bible. His life is also part of the history of the Netherlands.