one word

Un mot et tout est sauvé. Un mot et tout est perdu.

[One word and all is saved. One word and all is lost.]

—André Breton

learn it and die

Solon of Athens (c.640-560 BCE), the great lawmaker and reformer, attended a banquet where he heard a young man sing a poem by Sappho. Upon hearing the song Solon asked the boy to teach it to him. When others at the table asked Solon why he was so keen on knowing that song, he replied: "I want to learn it and die.

[Anecdote told in various classical sources.]