Hume's empiricist philosophy grounds all knowledge in impressions — the immediate data of sensory experience — before ideas, which are copies of impressions, and this epistemology runs through the Imagist movement's demand for direct, concrete, sensory images unmediated by abstraction; In Keats, the impression is philosophically valued as the site of genuine encounter with reality — the "Adam's dream" of beauty, where the impression of the beloved is so vivid that it seems to guarantee the reality of an ideal world; A poet working in the tradition of Japanese haiku brings the impression to philosophical precision — the single, sharp sensory impression that yields a moment of perception not commentary — and this tradition informs Western poets' interest in the impression as an epistemological unit; Wordsworth's "spots of time" are philosophical accounts of powerful impressions — sensory encounters so intense that they leave permanent traces in the developing consciousness and continue to nourish it throughout life; The French Impressionist movement in painting influenced contemporary poetry, particularly in the work of Frank O'Hara and the New York School, where the poem attempts to capture the impression of a moment — its specific light, mood, and contingency — before it passes; Phenomenological aesthetics (Ingarden, Merleau-Ponty) treats the aesthetic impression as a complex, layered experience that involves sensory, cognitive, emotional, and imaginative dimensions — the poem's impression is not a simple sensory datum but a richly structured event of consciousness