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“A thing of beauty is a joy for ever.”
Keats opens the poem by claiming that beauty can continue to give delight beyond the instant in which it is first encountered.
Source note: Endymion, Book I, opening line; Project Gutenberg #24280. This is a poetic proposition within a Romantic work, not an empirical rule that every aesthetic experience remains pleasurable forever.
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“Its loveliness increases; it will never pass into nothingness”
The continuation imagines beauty as something whose value can deepen in memory and imagination rather than simply fading with the moment.
Source note: Endymion, Book I; Project Gutenberg #24280. The line directly continues “A thing of beauty is a joy for ever” and belongs to the poem’s idealizing Romantic account of beauty.