In Theory of Moral Sentiments, Adam Smith reasons about how a change in one thing, A, is attended by a change in another thing, B. In expounding on such bivariate relationships, Smith sometimes seems to go out of his way to posit a state of the world in which the relationship would break down. That feature suggests an irony about knowing how a change in B attends a change in A. We might think we understand the bivariate relationship, but it holds only for certain states of the world. The relationship is circumstanced. The more one studies the Moral Sentiments, the more one realizes that circumstantiality suffuses its teachings. In this paper I suggest that Smith’s subtle handling of circumstantiality may help us appreciate some of his deepest themes, including the pretense of knowledge, the worthiness of liberal principles, and the difficulty of fostering virtue in our modern complex world. By puzzles, curious illustrations, Stoical foils, and other means, perhaps Smith found a way to hide circumstantiality from tyros, who might be discouraged by it, and to teach it to others. Also, the paper arrives at the question of the circumstances for competent moral self-estimation, and suggests that Smith’s words on friendship, virtue, frankness, and openness are worth taking to heart
