Materials about which to exercise its discursive Faculty. (Essay I.II.15)
As we come to remember particular experiences through repetition, we start to be able to label them. From there, we can abstract from the individual cases to talk about ‘types’ of experience, e.g. we move from ‘red’, ‘yellow’, ‘blue’ and so on, to the idea of ‘colour’.
But what does Locke mean when he says that the senses let in ideas? We often contrast an idea with a sensation: the sensation of yellow isn’t the same thing as the concept
YELLOW (When I am referring to a concept, I will put the word in capitals). When we see something yellow, this perceptual experience is quite different from the role
YELLOW plays in the thought ‘If it is yellow, it is coloured’. But Locke doesn’t mark this distinction strongly, which is confusing.
Hume corrects this mistake (we will use his terminology from now on). Like Locke,
Hume believes that we are immediately and directly aware of ‘perceptions’ (An An Enquiry concerning Human Understanding, § 2) ‘Perceptions’ are divided into ‘impressions’ and
‘ideas’. And both Locke and Hume divide impressions are divided into impressions of
‘sensation’ and those of ‘reflection’. Impressions of sensation derive from our senses, e.g. seeing a car; impressions of reflection derive from our experience of our mind, e.g. feeling emotions. (Locke also includes awareness of mental processes, e.g. reasoning, believing, willing, and so on.)
Hume then argues that ideas are ‘faint copies’ of impressions. Think what it is like to see a scene or hear a tune; now what it is like to imagine or