Variants: — It is not the size of the dog in the fight that counts, but the fight in the dog that matters. — "Stub Ends of Thoughts" by Arthur G. Lewis, a collection of sayings, in Book of the Royal Blue Vol. 14, No. 7 (April 1911), cited as the earliest known occurrence in The Dictionary of Modern Proverbs, edited by Charles Clay Doyle, Wolfgang Mieder, and Fred R. Shapiro, p. 232 — It is not the size of the dog in the fight that counts, but the fight in the dog that wins. — Anonymous quote in https://en.wikiquote.org/wiki/Mark_Twain