For 10 points, name this Dutch Jewish author of Ethics.
This philosopher argued that there can only be one substance because, via an ontological argument, a single substance must have both the attributes of "thinking" and "extension". This thinker's idea of mens una resembles Rousseau's concept of the general will. The Esnoga issued a cherem on this man for his assertion that (*) Ezra wrote the Torah. He posited a Hobbesian view on the state of nature and argued that a democracy was the best form of government in his Tractatus Theologico-Politicus. For 10 points, name this Dutch Jewish author of Ethics.
This philosopher argued that there can only be one substance because, via an ontological argument, a single substance must have both the attributes of "thinking" and "extension".
Baruch Spinoza [accept Benedito de Espinosa or Benedict de Spinoza]