Art that is happy to be Art
Artworks should have legs to run away the material world. Every drawing is a mundane step on a path that's pretty long.
Trunk and thigh are equal as well as thighs and legs.
So, the middle of the body seems to be somewhere on the lower half of the body.
To measure a thing is to tame it, to make it susceptible to your rules.
From an evolutionary standpoint, distributing anatomical responsibility is a good strategy, because it would not be a good design principle to have an Achilles' heel.
One theoretical framework that seems to fit well with current empirical data suggests that you do better by finding by yourself what looks right or not.