The more such longings are satisfied, the more they must grow and become a craze which sharpens the feeling of dissatisfaction.
"Psychology and Social Sanity"
Hugo Münsterberg
Being sightless sharpens other faculties.
"The Hidden Places"
Bertrand W. Sinclair
In such a position a man has not the courage to insult a woman, and, instead of answering, I set to work at once, without meeting even with that show of resistance which sharpens the appetite.
"The Memoires of Casanova, Complete The Rare Unabridged London Edition Of 1894, plus An Unpublished Chapter of History, By Arthur Symons"
Jacques Casanova de Seingalt