Deliberation is the process through which we decide what do to, or what to believe. When we think about what to do, we are engaged in practical deliberation. Theoretical deliberation is when we think about what to believe, or about which judgement to make.

Professor Sutton's thought-provoking book is directed principally to the question: ‘Are simple mathematical models helpful in economics, or are they misleading?’ His answer, baldly stated, is that if they are made right they are helpful, but if they are made wrong they are misleading.

He has in mind an ideal reader: someone who already knows from other fields how a successful theory based on formal mathematical models works, but who has only recently stumbled on economics, and is skeptical about formal mathematical models here. I am not quite an ideal reader now, but I was once, because I studied and worked in physics before going into economics.

We present the first comprehensive theory of fairness that conceives of fairness as having two dimensions: a comparative and an absolute one. The comparative dimension of fairness has traditionally been the main interest of Broomean fairness theories. It has been analysed as satisfying competing individual claims in proportion to their respective strengths. And yet, many key contributors to Broomean fairness agree that ‘absolute’ fairness is important as well. We make this concern precise by introducing the Fairness formula and the absolute priority rule and analyse their implications for comparative fairness.

This article refines a foundational tenet of rational choice theory known as the principle of description invariance. Attempts to apply this principle to human agents with imperfect knowledge have paid insufficient attention to two aspects: first, agents’ epistemic situations, i.e. whether and when they recognize alternative descriptions of an object to be equivalent; and second, the individuation of objects of description, i.e. whether and when objects count as the same or different. An important consequence is that many apparent ‘framing effects’ may not violate the principle of description invariance, and the subjects of these effects may not be irrational.

In A Treatise of Human Nature, Hume argues that morality pertains primarily to character, and that actions have moral content only to the extent that they signal good or bad character. I formalize his signalling theory of moral/immoral actions using simple game-theoretic models. Conditions exist under which there is a separating equilibrium in which actions do indeed credibly signal character, but conditions also exist in which there is only a pooling or semi-separating equilibrium. A tradeoff is identified between the signalling value of actions, and the consequentialist goal of incentivizing all character types to choose beneficial actions.