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.

If there is to be peace, Palestinians will have to unlearn the hatred of Israel they have imbibed during nearly two decades of Hamas rule. This will be a difficult task, but Cole Aronson argues, drawing on the experiences of World War II, that Israel has already gotten off to a strong start:

The population’s compliance can . . . be won by a new regime that satisfies its immediate material needs, even if that new regime is sponsored by a government until recently at war with the population’s former regime. Axis civilians were made needy through bombing. Peaceful compliance with the Allies became a good alternative to supporting violent resistance to the Allies.

Israel’s current campaign makes a moderate Gaza more likely, not less. Destroying Hamas not only deprives Islamists of the ability to rule—it proves the futility of armed resistance to Israel, a condition for peace. The destruction of buildings not only deprives Hamas of its hideouts. It also gives ordinary Palestinians strong reasons to shun groups planning to replicate Hamas’s behavior.