A human being is an ingenious assembly of portable plumbing.

Morley’s quip reduces the lofty idea of “human nature” to a comic, bodily fact: we are, in large part, systems for moving fluids and waste. The humor comes from applying the language of engineering—“ingenious assembly,” “portable plumbing”—to the human body, deflating pretension and reminding readers of our shared physicality. It also hints at a modern, mechanistic view of life (the body as apparatus), while keeping the tone light rather than grim. As a piece of epigrammatic wit, it functions as a corrective to self-importance and an invitation to humility grounded in biology.