Knowledge is the treasure of a wise man.

Penn’s aphorism treats knowledge as a form of wealth that cannot be seized, spent down, or lost through ordinary misfortune. By calling it the “treasure” of the wise, the line implies that wisdom is measured less by possessions or status than by cultivated understanding and judgment. In Penn’s moral vocabulary, “treasure” also carries an ethical charge: what one values most shapes one’s character and conduct. The saying thus commends learning not as ornament but as a durable inner resource—something that guides action, steadies the mind, and outlasts material fortunes.