The question of common sense is always what is it good for? — a question which would abolish the rose and be answered triumphantly by the cabbage.

Lowell satirizes a narrowly utilitarian idea of “common sense” that judges everything by immediate practical payoff. By imagining such a mindset asking of a rose, “What is it good for?”, he exposes how this kind of reasoning would discard beauty, delight, and symbolic value as useless. The cabbage—edible, serviceable, and easily justified—“answers triumphantly,” standing for the triumph of practicality over imagination. The line defends art and the non-instrumental goods of life (beauty, poetry, ideals) against a culture that measures worth only by utility, warning that such “sense” can become a form of spiritual impoverishment.