[W]hy do we inflict pain for no gain? On the face of it, it is rather a perverse way of going about things. Does spitefulness stem from an affronted sense of fairness? Or something altogether darker: envy, lust for revenge – or perhaps even pure sadism?
It might be all those things. Economists, anthropologists and evolutionary biologists have been teasing out how, used judiciously, spiteful behaviour can be one of our best weapons in maintaining a fair and ordered society. But intentions that are noble in one situation can be malicious in another – making spite a weapon that can all too easily backfire.
Human spite is a complex affair. It is not pure selfishness in the Darwinian sense, like a stag that picks a fight with another. Though it might be gored in the process, the stag is actually acting in its own best interests. If it ends up with more mates, then the chances of passing on its genes are increased, an evolutionary prize worth fighting for.