Routledge History of Philosophy Volume IV

278 RENAISSANCE AND SEVENTEENTH-CENTURY RATIONALISM
knowledge, what he says about such knowledge can be illuminated by comparing
it with what Descartes says about his famous utterance, Cogito, ergo sum. It is
well known that Descartes denied that, in saying ‘I am thinking, therefore I
exist’, he was deriving existence from thought by a kind of syllogism.
(‘Everything that thinks, exists; I am a being that thinks; therefore…etc.’) (Reply
to Second Objections, CSM ii, 100). Rather, he said that he recognized his
existence ‘as something self-evident by a simple intuition of the mind’ (ibid.).
This may seem to involve him in a difficulty which is similar to Spinoza’s:
namely, that Descartes expresses this ‘simple intuition’ in what appears to be the
form of an inference, in that it involves the term ‘therefore’. What is of great
interest here is the solution that Descartes offered in his conversation of 1648
with the young Dutch scholar Frans Burman. 88 Burman had asked about the
nature of Cogito, ergo sum; in his reply, Descartes said that the universal
proposition ‘Everything that thinks, exists’ is logically prior to ‘I am thinking,
therefore I exist’, but that I do not need to know the former proposition before I
can recognize the truth of the latter. He went on to say, ‘We do not separate out
these general propositions from the particular instances; rather, it is in the
particular instances that we think them’. Now, it is not suggested here that
Spinoza knew of Descartes’s conversation with Burman, 89 or indeed that he
would have regarded Cogito, ergo sum as an instance of the third kind of
knowledge. The point is simply that we can make sense of what he says about
intuitive knowledge by supposing him to be thinking along lines similar to those
followed by Descartes. That is, when Spinoza says that, in order to discover a
fourth proportional, we do not have to appeal to a universal rule but can make
use of intuitive knowledge, what he means can be put in Descartes’s terms by
saying that we think of the general rule in the particular instance.
The question now arises whether the Ethics contains any substantive examples
of the third kind of knowledge, or whether it, at best, only points the way
towards such knowledge. There is of course the case of the discovery of a fourth
proportional; but this is merely illustrative, and does not play an essential part in
the structure of the work. However, there does seem to be an important use of
intuitive knowledge in the Ethics. This is to be found in Proposition 36 of Part V,
together with its Corollary and Scholium. In the Scholium, Spinoza remarks that,
from what he has said elsewhere in the work, ‘It is quite clear to us how and in what
way our mind follows with regard to essence and existence from the divine
nature and continually depends on God’, and he continues by saying that this is
an example of the third kind of knowledge. The Scholium does more than give
an example of the third kind of knowledge; it also shows precisely how this kind
of knowledge differs from the second, and why Spinoza ascribes such
importance to it. Spinoza says (ibid.) that, in the first part of the Ethics, he has
already shown 90 that ‘all things (and consequently the human mind) depend on
God with regard to essence and existence’. This, he says, is an example of the
second kind of knowledge; what is more, the proof of this proposition is
‘perfectly legitimate and placed beyond the reach of doubt’. We have, then, no