(one's) better nature

The best aspects of one's character, especially one's generosity, magnanimity, mercy, or empathy. I wouldn't bother trying to appeal to his better nature—the boss doesn't look on requests for charity lightly. With this fundraiser, we're hoping people's better nature shines through to help the millions in need following the natural disaster.

your better nature

the good side of your character; your capacity for tolerance, generosity, or sympathy.

1995 Daily Mail Pollard is thrown out of the Woolpack and tries to weasel his way back in by appealing to Caroline's better nature.