Treat a man as he is and he will remain as he is. Treat a man as he can and should be and he will become as he can and should be.

The aphorism contrasts two ways of relating to others: a static, descriptive stance that accepts people only as they presently appear, and a developmental stance that addresses their latent capacities and moral possibilities. It suggests that expectations and treatment can be self-fulfilling—when we interact with someone as if growth is possible and expected, we create conditions (trust, responsibility, encouragement, challenge) that make improvement more likely. In leadership, education, and parenting, the line argues for “seeing” people in terms of potential rather than deficits, while also implying an ethical dimension (“should be”) that ties personal development to character and responsibility.