"Spinoza is the noblest and most lovable of the great philosophers ... Spinoza's maxims are probably the best possible."

One of Bertrand Russell's best-loved philosophers was the Dutch optical lens grinder of Sephardic Jewish origin Baruch Spinoza ― below are excerpts from Russell's A History of Western Philosophy (1945), Book Three. Modern Philosophy, Ch. X: Spinoza, pp. 569-80
"Spinoza (1634-77) is the noblest and most lovable of the great philosophers. Intellectually, some others have surpassed him, but ethically he is supreme. As a natural consequence, he was considered, during his lifetime and for a century after his death, a man of appalling wickedness."
p. 569
"... Spinoza's maxims are probably the best possible. Take, for instance, death: nothing that a man can do will make him immortal, and it is, therefore, futile to spend time in fear and lamentations over the fact that we must die. To be obsessed by the fear of death is a kind of slavery; Spinoza is right in saying that "the free man thinks of nothing less than of death." But even in this case, it is only death in general that should be so treated; death of any particular disease should, if possible, be averted by submitting to medical care. Even in this case, what should be avoided is a certain kind of anxiety or terror; the necessary measures should be taken calmly, and our thoughts should, as far as possible, be directed to other matters. The same considerations apply to all other purely personal misfortunes."
p. 578
"Spinoza is in the right—a life dominated by a single passion is a narrow life, incompatible with every kind of wisdom. Revenge as such is therefore not the best reaction to injury."
p. 579
"Spinoza thinks that, if you see your misfortunes as they are in reality, as part of the concatenation of causes stretching from the beginning of time to the end, you will see that they are only misfortunes to you, not to the universe, to which they are merely passing discords heightening an ultimate harmony. I cannot accept this; I think that particular events are what they are, and do not become different by absorption into a whole. Each act of cruelty is eternally a part of the universe; nothing that happens later can make that act good rather than bad or can confer perfection on the whole of which it is a part.
Nevertheless, when it is your lot to have to endure something that is (or seems to you) worse than an ordinary lot of mankind, Spinoza's principle of thinking about the whole, or at any rate about larger matters than your own grief, is a useful one. There are even times when it is comforting to reflect that human life, with all that it contains evil and suffering, is a tiny part of the life of the universe. Such reflections may not suffice to constitute a religion, but in a painful world they are a help towards sanity and an antidote to the paralysis of utter despair."
p. 580
"I like mathematics because it is not human and has nothing particular to do with this planet or with the whole accidental universe – because, like Spinoza's God, it won't love us in return."
― Bertrand Russell, Letter to Lady Ottoline Morrell (March 1912) as quoted in Gaither's Dictionary of Scientific Quotations (2012), p. 1318
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Image: Detail from a portrait of a man (thought to be Baruch Spinoza) private collection.
Baruch Spinoza (4 November 1632 – 21 February 1677) was a Dutch philosopher. The breadth and importance of Spinoza's work was not fully realized until many years after his death. By laying the groundwork for the 18th-century Enlightenment and modern biblical criticism, including modern conceptions of the self and, arguably, the universe, he came to be considered one of the great rationalists of 17th-century philosophy. Inspired by the groundbreaking ideas of René Descartes, Spinoza can rightfully lay claim as a leading figure of the Dutch Golden Age. His magnum opus, the posthumous Ethics, in which he opposed Descartes' mind–body dualism, has earned him recognition as one of Western philosophy's most important thinkers. Philosopher Georg Wilhelm Friedrich (G.W.F. Hegel) said of all contemporary philosophers, "You are either a Spinozist or not a philosopher at all."
Spinoza argued that God exists yet is abstract and impersonal. He claimed that everything is a derivative of God, interconnected with all of existence. Although humans only experience thought and extension, what happens to one aspect of existence will still affect others. Thus, Spinozism teaches a form of determinism and ecology and supports this as a basis for morality. Spinoza was often considered to be an atheist because he used the word "God" (Deus) to signify a concept that was different from that of traditional Judeo–Christian-Islamic monotheism. Thus, Spinoza's cool, indifferent God is the antithesis to the concept of an anthropomorphic, fatherly deity who cares about humanity.
"If I had as clear an idea of ghosts, as I have of a triangle or a circle, I should not in the least hesitate to affirm that God had created them; but as the idea, I possess of them is just like the ideas, which my imagination forms of harpies, griffins, hydras, &c., I cannot consider them as anything but dreams, which differ from God as totally as that which does not differ from that which is."
– Baruch Spinoza, Letter to Hugo Boxel (October 1674) The Chief Works of Benedict de Spinoza (1891) Tr. R. H. M. Elwes, Vol. 2, Letter 58 (54)
Spinoza was frequently called an "atheist" by contemporaries, although nowhere in his work does Spinoza argue against the existence of God. Spinoza lived an outwardly simple life as an optical lens grinder, collaborating on microscope and telescope lens designs with Constantijn and Christiaan Huygens. He turned down rewards and honors throughout his life, including prestigious teaching positions. He died at the age of 44 in 1677 from a lung illness, perhaps tuberculosis or silicosis exacerbated by the inhalation of fine glass dust while grinding lenses. He is buried in the Christian churchyard of Nieuwe Kerk in The Hague.
In June 1678—just over a year after Spinoza's death—the States of Holland banned his entire works since they "contain very many profane, blasphemous and atheistic propositions." The prohibition included the owning, reading, distribution, copying, and restating of Spinoza's books, and even the reworking of his fundamental ideas. Shortly after (1679/1690) his books were added to the Catholic Church's Index of Forbidden Books.
Today Spinoza is a highly important historical figure in the Netherlands, where his portrait was featured prominently on the Dutch 1000-guilder banknote, legal tender until the euro was introduced in 2002. The highest and most prestigious scientific award of the Netherlands is named the Spinozaprijs (Spinoza prize). Spinoza was included in a 50-theme canon that attempts to summarise the history of the Netherlands. In 2014 a copy of Spinoza's Tractatus Theologico-Politicus was presented to the Chair of the Dutch Parliament and shared a shelf with the Bible and the Quran.