human nature; humanity; humanism
Refers to the inherent qualities, instincts, or moral nature of humans. Often used in philosophical, ethical, or literary contexts. 'Humanism' is a less common gloss, typically in discussions of humanistic thought.
He thinks deeply about the good and evil of human nature.
この小説は人性の複雑さを描いている。
This novel depicts the complexity of human nature.
senile; age-related
From 人 (human) + 性 (nature, character). The exact historical derivation is uncertain, but the kanji compound directly conveys the meaning of 'human nature'.