How is writing like kissing?

I can't write without a reader. It's precisely like a kiss—you can't do it alone.

John Cheever, quoted in Colin Robinson, "The Loneliness of the Long-Distance Reader, New York Times Sunday Review, Jan. 5, 2014, at 6, and quoted in turn in John Sutherland, "Literature and the Library in the Nineteenth Century," in Alice Crawford, ed., The Meaning of the Library (Princeton, N.J.: Princeton Univ. Press, 2015), p.