The central, unifying theme of Prentice Alvin is learning how to become an adult, how to use one's power to make the world better, and how to cultivate love and friendship while doing so.

One main expression of this theme is in the contrast between characters like Alvin and Peggy—who think in terms of long-range goodness for everyone—and the more limited thinkers like Makepeace Smith and Cavil Planter. Alvin and Peggy want to do good and to cultivate friendship because they know that in the long run this will bring them happiness. Makepeace Smith lets his passions rule him, wanting to be thought right, to exercise power, and to have wealth, and in the process he loses love, respect, and friendship from those people who are most important to him. Cavil Planter, a southern plantation owner, lets himself be deceived...