In Walter Isaacson's biography of Benjamin Franklin, the author explores a key theme reflecting Franklin's insights into human nature: the tendency to rationalize actions that serve personal convenience. This observation appears consistently throughout Franklin's autobiography, tales, and various almanacs, showcasing an enduring interest in how people justify their choices.

Franklin's wit and wisdom reveal a deep understanding of moral flexibility, illustrating how individuals often prioritize their needs over ethical considerations. Isaacson captures this aspect of Franklin's character, highlighting the humor and irony inherent in our self-deceptions, a recurring motif that defines much of Franklin's reflections on society and human behavior.