If you know the enemy and know yourself, you need not fear the result of a hundred battles.

Sun Tzu · The Art of War, chapter III, in Lionel Giles's 1910 translation, the standard English text.

More Wisdom Quotes

I firmly believe that love [of a subject or hobby] is a better teacher than a sense of duty—at least for me.

Albert Einstein · From a 1940 draft letter to his friend the physicist Philipp Frank; the shared "Love is a better teacher than duty" is a shortening, and the bracketed gloss is the editor's.

Keep love in your heart. A life without it is like a sunless garden when the flowers are dead.

Attributed to Oscar Wilde · Recorded by Harold Mellor, a friend who travelled with Wilde in 1898 to 1900, and printed only in 1949 in the Marquess of Queensberry's Oscar Wilde and the Black Douglas; Quote Investigator finds it plausible but resting on one man's memory half a century on.

A successful marriage requires falling in love many times, always with the same person.

Mignon McLaughlin · An aphorism from the second collection of the Glamour editor's "Neurotic's Notebook" sayings.

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We Value Your Opinion Comments

“If you know the enemy and know yourself, you need not fear the result of a hundred battles.”

“I firmly believe that love [of a subject or hobby] is a better teacher than a sense of duty—at least for me.”

“Keep love in your heart. A life without it is like a sunless garden when the flowers are dead.”

“A successful marriage requires falling in love many times, always with the same person.”

We Value Your Opinion Comments

If you know the enemy and know yourself, you need not fear the result of a hundred battles.

I firmly believe that love [of a subject or hobby] is a better teacher than a sense of duty—at least for me.

Keep love in your heart. A life without it is like a sunless garden when the flowers are dead.

A successful marriage requires falling in love many times, always with the same person.