Indicates a time, stage, or manner (e.g., 'at the time of / at the stage of'); a formal or literary usage (as in 'only upon completion...').
完成にして初めて、その設計の良さがわかった。
Only upon completion did I understand the quality of the design.
開園にして多くの人が訪れた。
At the opening, many people visited.
Can express a concessive meaning ('despite; although; even'), often in formal or literary contexts.
十歳にしてすでに高度な技術を持っているとは驚きだ。
It's surprising that at only ten years old he already possesses advanced skills.
若くして成功した彼の話は人々を励ました。
His story of succeeding at a young age encouraged people.
Used to list two roles or attributes ('as well as; both ... and ...'), e.g., 'teacher and also a writer'.
彼は教師にして作家でもある。
He is both a teacher and a writer.
彼女は医者にして三児の母でもある。
She is a doctor and also a mother of three.
An archaic sense meaning 'at/in/on' (indicating location); rarely used in modern Japanese.
古い文に見る『都にして栄えたり』の用法は現在ではあまり使われない。
The usage like 'flourished in the capital' seen in old texts is seldom used today.
文語的表現として古い詩歌ににしての用法が残ることがある。
As a literary expression, the use of にして can sometimes remain in old poetry.