Examining the 17th-century philosopher’s continued grip on the modern imagination, and the dramatic story of his expulsion from the Amsterdam Sephardi community, Steven Nadler highlights those of his ideas that remain most relevant:

Spinoza is one of history’s most eloquent advocates for freedom and toleration. The ultimate goal of the Theological-Political Treatise is enshrined in both the book’s subtitle and in the argument of its final chapter: to show that “freedom to philosophize may not only be allowed without danger to piety and the stability of the republic, but that it cannot be refused without destroying the peace of the republic and piety itself.”

All opinions whatsoever, including religious opinions, are to be absolutely free and unimpeded, both by necessity and by right. “It is impossible for the mind to be completely under another’s control; for no one is able to transfer to another his natural right or faculty to reason freely and to form his own judgment on any matters whatsoever, nor can he be compelled to do so.” Indeed, any effort by a sovereign to rule over the beliefs and opinions of citizens can only backfire, as it will ultimately serve to undermine the sovereign’s own authority. . . .

Spinoza’s argument for freedom of expression is based both on the right (or power) of citizens to speak as they desire, as well as on the fact that it would be counterproductive for a sovereign to try to restrain that freedom. No matter what laws are enacted against speech and other means of expression, citizens will continue to say what they believe, only now they will do so in secret. Any attempt to suppress freedom of expression will, once again, only weaken the bonds of loyalty that unite subjects to sovereign. In Spinoza’s view, intolerant laws lead ultimately to anger, revenge, and sedition.

While it is commendable that administrators of several universities finally called upon police to crack down on violent and disruptive anti-Israel protests, the actions they have taken may be insufficient. At Columbia, demonstrators reestablished their encampment on the main quad after it had been cleared by the police, and the university seems reluctant to use force again. The school also decided to hold classes remotely until the end of the semester. Such moves, whatever their merits, do nothing to fix the factors that allowed campuses to become hotbeds of pro-Hamas activism in the first place. The editors of National Review examine how things go to this point:

Since the 10/7 massacre, Columbia’s Jewish students have been forced to endure routine calls for their execution. It shouldn’t have taken the slaughter, rape, and brutalization of Israeli Jews to expose chants like “Globalize the intifada” and “Death to the Zionist state” as calls for violence, but the university refused to intervene on behalf of its besieged students. When an Israeli student was beaten with a stick outside Columbia’s library, it occasioned little soul-searching from faculty. Indeed, it served only as the impetus to establish an “Anti-Semitism Task Force,” which subsequently expressed “serious concerns” about the university’s commitment to enforcing its codes of conduct against anti-Semitic violators.

But little was done. Indeed, as late as last month the school served as host to speakers who praised the 10/7 attacks and even “hijacking airplanes” as “important tactics that the Palestinian resistance have engaged in.”

The school’s lackadaisical approach created a permission structure to menace and harass Jewish students, and that’s what happened. . . . Now is the time finally to do something about this kind of harassment and associated acts of trespass and disorder. Yale did the right thing when police cleared out an encampment [on Monday]. But Columbia remains a daily reminder of what happens when freaks and haters are allowed to impose their will on campus.