Of the Origin of Ideas
Perceptionsare the essence of human relationship with the world.
- Impressions: direct and clear products of
- Ideas: representations of previous impressions;
all our ideas or more feeble perceptions are copies of our impressions or more lively ones
No difference between impressions and ideas, only a question of force (Enquiry, II, §3).
There are no rules to know (unlike in Descartes’First Meditation), knowledge simply comes from the direct experience of and in the world; Hume is not saying how we have to acquire knowledge. We can’t have an idea without having had a previous corresponding impression.
Note: Hume uses “memory” as a synonym of “imagination”