Human nature is eternal. Therefore…

Human nature is eternal. Therefore, one who follows his nature keeps his original nature, in the end.

— Orson Welles, The Lady from Shanghai

Michael: Love. Do you believe in love at all, Mrs. Bannister?
Elsa: I was taught to think about love in Chinese.
Michael: The way a Frenchman thinks about laughter in French?
Elsa: The Chinese say, it is difficult for love to last long. Therefore, one who loves passionately is cured of love, in the end.
Michael: Sure, that's a hard way of thinking.
Elsa: There's more to the proverb: Human nature is eternal. Therefore, one who follows his nature keeps his original nature, in the end.