Hume's impressions

Scottish Empiricist, David Hume (1977: 9-13) proposed that Locke’s objections to innate ideas lack precision because his terms were “not chosen with caution, nor so exactly defined.” Hume differentiates between immediate “IMPRESSIONS” which he asserts “are innate,” and “IDEAS,” which are less vivid and after the fact:

Every one will allow, that there is a considerable difference between the perceptions of the mind, when a man feels the pain of excessive heat, or the pleasure of moderate warmth, and when he afterwards recalls to his memory this sensation, or anticipates it by his imagination. These faculties may mimic or copy the perceptions of the senses; but they never can entirely reach the force and vivacity of the original sentiment…

Here therefore we may divide all the perceptions of the mind into two classes or species, which are distinguished by their different degrees of force and vivacity. The less forcible and lively are commonly denominated THOUGHTS or IDEAS. The other species want a name in our language, and in most others; I suppose, because it was not a requisite for any, but philosophical purposes, to rank them under a general term or appellation. Let us therefore, use a little freedom, and call them IMPRESSIONS.

Hume, David. (1977) An Enquiry Concerning Human Understanding. First published: 1748. Hackett Publishing, Indianapolis.

Allan Ramsay (1766) Portrait of David Hume. Oil on canvas. National Galleries of Scotland.