Individuality, singularity, our unique personhood is something most people take for granted. It is the psychological underpinning of our ideas of freedom and liberty. It is the basis for our understanding of responsibility and ethical and moral behaviour.
We assume that people always had this definition of "individualism" and filter our understanding of the past through this concept. But the idea of the individual as we mean it is comparatively recent. It goes back no further than the middle of the 17th century and the man "who seeded the Enlightenment" (Professor Rebecca Newberger Goldstein's words, not mine) - Baruch Spinoza.
Spinoza is the first of the many modern Jewish thinkers who fundamentally altered the intellectual lens through which we reflect on and seek to understand our lives. His metaphysics, ethics and politics are focused on human beings as individuals, responsible for their own actions, not overseen or interacting with God.
But to bring out this idea of the individual he had to first demonstrate that the God of the Bible was a figure created by men from an imperfect knowledge of the nature of the universe, and wilful ignorance of how the Torah and Tanakh had been written.
From this demonstration, he could then prove that the clerics who claimed to speak and interpret God's law to the earthly rulers were operating on false pretences and should have nothing to do with the government.
In the middle of the 17th century this was brave thinking. It was also foolhardy.
Your community was your identity. Your individuality was circumscribed by the community's limitations. This was particularly true - then, as now - of Jews. Today, we have ample opportunity to mix as equals with people outside our community. But there is always a fear that we will take on too many of the characteristics of the wider society and in so doing lose some of our Jewishness. Even though we live in a secular age, the community can be fierce in policing what it means to be a good Jew.
In 17th-century Europe, the opportunities to mix were more limited and the insecurity of Jews about the way to behave among gentiles was exponentially higher. To stand as an individual in those circumstances was much more difficult.
Spinoza was not just a theoretician, in his life he lived out this tension between the conclusions of his philosophy, and the demands of the community into which he was born: Amsterdam's Sephardi community.
The testament to this tension is the most dramatic incident of his life, the decision: "Espinoza should be excommunicated and expelled from the people of Israel."
The philosopher was 23 when he was put in cherem, or excommunicated, by the elders of Amsterdam's Talmud Torah. The cherem document survives. It curses and damns him in great rhetorical detail but the specifics of the case are lost to history. People are still speculating about the reasons why. (There was a conference in Amsterdam last autumn to discuss the question - it can be watched online and is very interesting.)
Rabbi Pinchas Toledano, current leader of Amsterdam's Sephardi community, says it is obvious why Spinoza was expelled. "He says there is no God, except in a philosophical way. He says the law of Moses is no longer divine." Rabbi Toledano adds: "I would have put him in cherem."
But the 23-year-old Spinoza had not written anything yet. How did the rabbis who pronounced the cherem know what he thought? From conversation with him?
Another possible reason is the "What will the goyim think" explanation. Amsterdam's Sephardi community was relatively new. For the previous century-and-a-half they had been wanderers. Many had had to convert to Catholicism to remain in whatever place they had tried to live. Now they had safe haven and the right to practise Judaism. The community was worried that harbouring an atheist and free thinker might jeopardise this arrangement with their Dutch rulers.
Professor Piet Steenbakkers, who holds the chair in Spinoza Studies at Erasmus University, speculates that it might have been something more mundane. After his father died, Spinoza inherited the family business. It was bankrupt. He then went to Amsterdam municipal court to have himself declared an orphan - to get protection from his father's creditors. Using a Dutch court rather than the Beth Din violated community norms. Jews used the Jewish court. Going to law in the Dutch court may have been a step too far into integration.
Steenbakkers explains that, as a merchant, running a business importing fruit from the Mediterranean, Spinoza had daily contact with non-Jews. The Netherlands offered tolerance not only to Jews but to dissenting Protestants of all persuasions. They, too, were in business and Spinoza dealt with them daily. At the time of the cherem, Spinoza was spending a great deal of time with dissenters.
He may have found that he had more in common with their ideas about the relationship of God, Man and the State than with his own community, obedient as it was to rabbinical authority.
In any case, he doesn't seem to have been bothered by his expulsion. The philosopher told a friend: "They do not force me to do anything that I would not have done of my own accord if I did not dread scandal. But, since they want it that way, I enter gladly on the path this opened to me, with the consolation that my departure will be more innocent than was the exodus of the early Hebrews from Egypt."
So Spinoza walked his path. A singular man. He tried to create a space for himself where he was beholden to no one. He turned down a handsome annuity and the chair of philosophy at Heidelberg University because he thought both might interfere with his ability to be a free individual.
In one way or another, Spinoza set an example for every person who leaves the comforting certainty of community behind in making his or her way through life. In particular, he set the example for the great Jewish thinkers who would emerge in the Ashkenazi world in the century after the end of ghetto-isation, like Freud and Einstein.
The difference of course is that the modern Jewish identity is - more or less - reconciled with the free-thinking of the Spinozas in our midst. So Einstein could be embraced by the community and yet write to Rabbi Herbert Goldstein, in 1929, that he "believed in Spinoza's God."
