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originator; founder
この学派の創始者は彼だとされている。
He is considered the founder of this school of thought.
美術館で茶道の創始者を称える特別展が開催された。
A special exhibition celebrating the founder of the tea ceremony was held at the museum.
その思想の創始者は多大な影響を与えた。
The founder of that philosophy exerted a great influence.