Reason and Inquiry: The Erotetic Theory presents a unified theory of the human capacity for reasoning and decision-making. The erotetic theory accounts for a diverse range of empirically documented fallacies and framing effects. It shows how the same mental processes that yield fallacies can yield what logicians call first-order validity and probabilistic coherence in reasoning, as well as rational decision-making as conceived by economists.

The book's central idea is that our minds naturally aim at resolving issues, and if we are sufficiently inquisitive in the process, we can avoid mistakes. The erotetic theory holds that both the successes and the failures of reason are due to this aim. Rationality is secured if we reach what is described by the theory as erotetic equilibrium.