As Hume distinguished impressions from ideas, contemporary colloquial English distinguishes between percepts and the mental images that we experience when we fantasize, daydream, or recall some experience from memory.
Hume initially distinguishes impressions and ideas in terms of their degree of force and vivacity.
When Hume distinguishes impressions and ideas in terms of their relative force and vivacity, he is pointing out something that is generally true of them as a matter of fact.
Hume's attempt to distinguish impressions and ideas by their different degrees of vivacity has frequently been criticized as unclear and unconvincing (for instance famously by Ryle 1949), and his classification of dreams as ideas seems to exacerbate this problem (Waxman 1994; Broughton 2006).
The existence of the special character supposed to distinguish cognitive impressions from other impressions was the principal target of the Academics' arguments (see Section 3 of the entry on Carneades).
Thus, to distinguish one impression from another, we must give them separate locations.
In contrast, female newcomers and female veterans were distinguished on the impression items but were not categorized separately.
Freeman lists all known editions of Darwin's published works, providing precise bibliographical information on each, including, for instance, information about how to distinguish different impressions of the same works from one another.
Hume distinguishes two kinds of impressions: impressions of sensation, or original impressions, and impressions of reflection, or secondary impressions.
Cognitive impressions, then, are true impressions which are, in addition, distinguished by a special character that can belong to no false impression and that human beings can discriminate.
