Beauty of all kinds gives us a peculiar delight and satisfaction; as deformity produces pain, upon whatever subject it may be placed, and whether surveyed in an animate or inanimate object.
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It would seem, that the very essence of beauty consists in its power of producing pleasure. All its effects, therefore, must proceed from this circumstance: And if beauty is so universally the subject of vanity, it is only from its being the cause of pleasure.
Another evident demonstration from Hume, who proceeds by observation: beauty simply produces pleasure; no need to rationalize further.
Beauty, in this sense, has no direct explanation: we like or we don’t like (something or someone). We are born with certain tendencies, we develop some over time, but the pleasure from beauty will always be given from the senses. We cannot do otherwise but listen to what we find beautiful, hence what brings us pleasure.
To like something, finding it beautiful, does not rely on will, on volition, says Hume; it is not something that we chose rationally, but rather something that we undergo, like the laws of nature.