- problems with rationalism
- (1) Hume criticised rationalism by claiming that the a priori knowledge that Descartes sets so much store by cannot be substantive knowledge of the world, as it will only tell us about the connections between ideas – what he calls ‘relations of ideas’. Such knowledge turns out to be concerned with definitions, and logical and mathematical relations.
- (2) Matters of fact, on the other hand, are substantial truths about the world but can only be obtained through experience. Hume also denied Descartes’ doctrine of innate ideas and insisted all ideas were based on sense impressions.
- (3) Hume has in mind here many of the claims made by the rationalist philosophers. For example, Spinoza says: The more we understand individual things the more we understand God.
- (4) How does Hume explain the feeling that there is necessity in sequences of natural events? Our feeling of necessity at work in nature is ultimately illusory according to Hume.Because ideas are copies of impressions, the force and frequency of similar impressions determines how vividly the resulting ideas are imprinted on the mind. Repeated experience ingrains ideas and triggers feelings of expectation, which we mistake for necessity.
- In terms of Hume’s Fork this claim does not do well. Firstly, is it a matter of fact? If so then the ideas it expresses should be knowable either through ‘outward sense’ or ‘inner sentiment’. This is clearly not so, for what sense impressions or inner feelings could possibly lead us to accept its truth? Secondly, does the statement express a relation of ideas? If so then it will be possible to either demonstrate its truth, as, for example, we can demonstrate Pythagoras’ theorem – or it will be intuitively obvious.