All growth depends upon activity. There is no development physically or intellectually without effort, and effort means work.

The quotation expresses a characteristically Coolidgean ethic: progress—whether bodily, mental, or civic—does not occur passively but through sustained exertion. By pairing “physically” and “intellectually,” it rejects the idea that education or self-improvement is merely a matter of talent or circumstance; it is instead the product of disciplined action. The final clause (“effort means work”) strips away euphemism and sentimentality, insisting that real advancement has a cost in labor and persistence. In a broader American context, the line aligns with traditions of self-reliance and the moral valuation of work, framing activity as the engine of both personal development and social achievement.