noun
nature; disposition; temperament
Refers to a person's inherent mental or emotional character; somewhat literary or formal in tone.
彼の心術は穏やかで、誰とでもすぐに打ち解ける。
His nature is gentle, and he quickly gets along with anyone.
心術の違いが、二人の意見の対立を生んだ。
The difference in their temperaments caused the clash of opinions.