Favorite Epigrams?

Two of my favorite epigrams:

• In theory, there is no difference between theory and practice, but in practice, there is. -- Jan L. A. van de Snepscheut
• The string is a stark data structure and everywhere it is passed there is much duplication of process. It is a perfect vehicle for hiding information. -- Alan J. Perlis

What about yours?

[Updated to add:]

‘Tis not in mortals to command success,
But we’ll do more, Sempronius – we’ll deserve it.
-- Joseph Addison’s Cato, a Tragedy (1712)

Comments

[Jason R Tibbetts]

Quem recitas meus est, o Fidentine, libellus:
Sed male cum recitas, incipit esse tuus.

"The book you're reading, Fidentinus, is mine,
But when you read it that poorly, it becomes yours."

-- Martial, Epigram I.XXXVIII, ca. 81 AD

[Andrew (he/him)]

The future ain't what it used to be. -- Yogi Berra