理をもって非に落ちる
also: りをもちてひにおちる
Meanings
1
lose an argument despite being in the right; have right on one's side yet succumb
rare term
Proverb-like expression meaning that even when one's position is logically or morally correct, one may still lose the dispute or be defeated. Rare and somewhat literary.
Sometimes you can lose an argument even when you're in the right, so strategy is also necessary in debates.