[W]hen we observe, as we must allow, that art is no better at one age than at another, but only different; that it is subject to modification, but certainly not to development; may we not safely accept this stationary quality as a proof that there does exist, out of sight, unattained and unattainable, a positive norm of poetic beauty? We cannot define it, but in each generation all excellence must be the result of a relation to it. It is the moon, heavily wrapt up in clouds, and impossible exactly to locate, yet revealed by the light it throws on distant portions of the sky.
Edmund Gosse, “On Fluctuations of Taste”