The Happiest of the Poets in Ideas of Good and Evil by William Butler Yeats.

“I often see him in my mind as I saw him once at Hammersmith holding up a glass of claret towards the light and saying, ‘Why do people say it is prosaic to get inspiration out of wine? Is it not the sunlight and the sap in the leaves? Are not grapes made by the sunlight and the sap?'” [via]