The greatest good is the knowledge of the union which the mind has with the whole nature. - Benedictus de Spinoza

I find no evidence that Jefferson read Spinoza, although his library does contain a copy of his works. Enlightenment thought is so saturated with Spinoza's ideas, however, that they could have reached Jefferson by innumerable routes.

The rise of Spinozism in the late eighteenth century is a phenomenon of no less significance than the emergence of Kantianism itself. By the beginning of the nineteenth century, Spinoza's philosophy had become the main competitor to Kant's, and only Spinoza had as many admirers or adherents as Kant.

The 21st of February of this year was the two hundred and fiftieth anniversary of the death of Benedict Spinoza. On that day a solemn celebration in Spinoza's memory was held under the auspices of the Spinoza Society (Societas Spinozana) in The Hague—the city where Spinoza spent the last years of his life where his ashes rest. At this grand meeting there were in attendance, besides official representatives of the universities and of science, official representative of the League of Nations, who demonstrated in his speech that if Spinoza were alive today he would be an ardent admirer of the League of Nations, since it strives for the realization of universal peace. A representative of the church—no celebration, as is well known, can get along there without a representative of the church—for his part, demonstrated that Spinoza's teaching does not in the least contradict the Christian religion. There were other speeches as well, but I shall not dwell on them. At all events, everyone was agreed that Spinoza was a great idealist, pantheist, and mystic, the founder of a new religion, etc. But at Hague no voice was raised to cry out loudly to all these fine gentlemen: 'You are impudent liars.'