A kiss can never be absolutely defined…
From The Art of Kissing: A 1936 Guide for Lovers
“A kiss can never be absolutely defined. Because each kiss is different from the one before and the one after. Just as no two people are alike, so are no two kisses alike. For it is people who make kisses. Real, live people pulsating with life and love and extreme happiness…”
(source— with a great book review, more hilarious quotes, and great links)