It is human nature to think wisely and act in an absurd fashion.

The remark distills a skeptical, ironic view of human rationality: people are capable of sound judgment in the abstract—offering prudent advice, forming clear principles, or recognizing what ought to be done—yet often behave irrationally when passions, habits, vanity, fear, or social pressures intervene. The contrast between “think wisely” and “act…absurd” highlights the gap between intellect and conduct, suggesting that reason is frequently overridden by impulse or circumstance. In a broader moral sense, the line implies that folly is not an exception but a recurring feature of ordinary life, and that self-knowledge should include humility about how rarely insight translates into consistent action.