Give up
If you can’t convince somebody, reassess your own situation: what will it
cost me if I give up now? A smiling confession of your own defeat comes
across as more self-assured than sullenness. And, what’s more, the less
interest you show, the less satisfied your adversary will feel.
‘Oysters open completely when the moon is full; and when the crab sees
one it throws a piece of stone or seaweed into it and the oyster cannot
close again, so that it serves the crab for meat. Such is the fate of him who
opens his mouth too much and thereby puts himself at the mercy of the
listener.’
Leonardo da Vinci