expression, ichidan verb
cannot just stand by and watch; cannot look on without doing something
Expresses that a situation is so troubling or pitiful that one feels compelled to intervene or help, rather than remain a passive observer.
See also: 見かねる
困っている人を見るに見かねて、助けに入った。
Unable to just watch someone in trouble, I stepped in to help.
彼のひどい態度を見るに見かねて、注意した。
I couldn't stand by and watch his terrible attitude, so I said something.