Control by hurtpeoplehurtpeople

A scorpion asks a frog to carry him over a river. The frog is afraid of being stung, but the scorpion argues that if it did so, both would sink and the scorpion would drown. The frog then agrees, but midway across the river the scorpion does indeed sting the frog, dooming them both. When asked why, the scorpion points out that this is its nature.