"One of the ideas that I play around with in the book [Betraying Spinoza: The Renegade Jew Who Gave Us Modernity] is tracing a possible path from Spinoza's influence in Amsterdam to the founding fathers of America, by way of John Locke, who spent time in Amsterdam a few years after Spinoza's death and fraternized with people of the same liberal persuasion as those in whom Spinoza had confided his ideas. No matter whether Madison and Jefferson really did read Spinoza (Spinoza was in Jefferson's library) they often sound just like him in their letters."