A habit is something you can do without thinking - which is why most of us have so many of them.

Clark’s quip hinges on the double meaning of “without thinking.” In a neutral sense, habits are automatic behaviors—skills and routines that no longer require conscious effort. But the punchline implies a moral and intellectual cost: because habits run on autopilot, people accumulate them easily, often without reflection, intention, or scrutiny. The line gently satirizes human complacency, suggesting that much of daily life is governed by unexamined patterns rather than deliberate choice. It also hints at why changing habits is difficult: what is unthinking is also unmonitored, and therefore resistant to correction until brought back into awareness.