It is generally agreed that modern Western philosophy begins with a story told by Descartes about himself:

His sense of certainty had been ‘beset by so many doubts and errors’, he wrote, that ‘I had gained nothing from my attempts to become educated but increasing recognition of my ignorance.’ From that point, his narrative became less straightforward and more contentious. God came into it. God's existence was proved from premises which he found undeniable: ‘I concluded that it is at least as certain as any geometrical proof that God … is or exists.’ God's existence and character seemed to underwrite or guarantee the rest of Descartes's knowledge.

The parallel story left to us by Spinoza is only a fragment of an early work. It sets off in an autobiographical tone reminiscent of Descartes, though even more reminiscent of a medieval confessional memoir: ‘After experience had taught me the hoUowness and futility of everything that is ordinarily encountered in daily life’, and the source of initial concern was entirely different from Descartes's: ‘and I realised that all the things which were the source and object of my anxiety held nothing of good and evil in themselves save in so far as the mind was influenced by them, I resolved at length to enquire whether there existed a true good’.