On looking for truth: Spinoza after Descartes

For anyone who has grown pessimistic about the prospect of ever understanding Spinoza, it is perhaps ironic that Spinoza himself holds that truth is self-evident, manifest, luminous. As he puts it, “truth requires no sign [veritas nullo egeat signo]” (TIE 36/G II 15); “truth is its own standard [veritas sui sit norma]”; someone who has a true idea “cannot doubt the truth of the thing”; and “a true idea involves the highest certainty” (E2p43&s/G II 123–125, cf. KV 2.15/G I 178–179). As a first pass, the thought seems to be that if you do have a true idea, there is nothing else you need to know or do in order to also know that the idea is true: there is no need for a comparison with the external world, or for vetting against some prior standard, no need to look for some mark of truth beyond the idea itself. To the question “how [...] can [someone] know that he has an idea that agrees with its object?” Spinoza replies with almost distressing serenity: “this arises solely from his having an idea that does agree with its object” (E2p43s/G II 124–125). Spinoza’s position would have been easier to accept if it were just a claim about foundational truths alone. Perhaps a philosophical system must indeed bottom out in something self-evident, on pain of an infinite regress. His doctrine would also have been easier to accept if it had expressed merely an ideal or standard of genuinely scientific true ideas: on such a reading, true ideas form a bona fide science once we can no longer doubt them (perhaps because of the strength of the inferential links between them). But Spinoza’s claim appears to be a claim about the nature of truths generally: it is any and all truths, even the most ordinary ones, that, it seems, are supposed to “requir[e] no sign”, “involve[e] the highest certainty” and “cannot [be subjected to] doubt.” 2773-0107