A proverb-like saying that love is beyond reason—it often leads to unexpected feelings or actions that can't be planned.
彼女が突然遠くへ行くと言い出した。恋は思案の外だとしか言いようがない。
She suddenly said she would leave for a distant place. All I can say is love is beyond reason.
普段は慎重な彼も、恋は思案の外で大胆な行動を取った。
Normally cautious, he acted boldly because love is beyond reason.
恋は思案の外というけれど、時には理性より気持ちが優先されることもある。
They say love is beyond reason; sometimes feelings take precedence over logic.