Wikipedia:You can't squeeze blood from a turnip

Source: Wikipedia, the free encyclopedia.
A turnip cannot be coaxed, squeezed, or cajoled into producing blood. All efforts at obtaining blood from this vegetable would be futile.

You can't squeeze blood from a turnip. – Anonymous

You can't get something out of someone who simply doesn't have it to give.

If a

standard remedy
exists for an editor who has done something wrong and the editor shows no sign of regretting the mistake, then go ahead and apply the standard remedy.

Extreme gestures of

policies
and rebuffs appropriate overtures. Some troublesome users do not want to change and the community's energies are limited.

Indeed, you really can't squeeze blood from a turnip.

See also