ABSTRACT
IN the first place, what is an idea? The simplest and most natural answer was given by Hume, when he defined it as the “faint copy” or image of an impression. As I watch the snow falling outside, the idea of summer arises by contrast; that is, the impression of sunny skies and singing birds repeats itself faintly for me. It is in quality the same, but fainter; and if I proceed to the thought that summer after all will come again, this belief is only a growing strength of the image. Thus the idea is explained as an image, and belief as a kind of idea. Nothing further remains except to deny the possibility of any kind of belief not explicable by this means, i.e. not capable of being represented as a vivid image.
