
It's the final sentence of the Tractatus Logico-Philosophicus. This is usually a concession of realism for the sake of the artist, as most artists would prefer to avoid drawing an animals genitals or anus themselves. I mean, if you're a successful actress and you go out of the house in a skirt and without underwear, knowing that paparazzi are just waiting for opportunities like this and that it has happened many times before, then there's really nobody you can blame for it but yourself. Wittgenstein I, if I recall correctly? My professor and textbook made a distinction between Wittgenstein I and Wittgenstein II.
