The Deep Structure of Law and Morality

Even the casual observer will note that law and morality resemble one another in numerous and striking ways. Both practices typically consist of rules with general applicability, which we perceive to have special importance in our lives and to provide us with personal mandates that can operate irrespective of at least some consequence. Both purport to provide us with reasons to act that can override other compelling ones that arise from personal interest. Both also contain a special normative vocabulary-including terms like "ought," "duty," "obligation," "excuse," "right," and the like1-the terms of which are essentially contestable2 and irreducible in meaning to any descriptive statements of natural fact.3 Yet we tend to believe that there can be no warranted difference in legal or moral judgment without some difference in the natural facts.4 And our moral and legal practices are pervaded, in similar ways, by standards that not only purport to provide us with reasons to act but also to criticize deviations in ways that imply the permissibility of certain forms of sanction or coercion5-as well as by a portfolio of standard excuses that operate to defeat such criticisms in strikingly similar ways.6 This Article argues that these resemblances are more than superficial. They arise from the fact that law and morality share a deep and pervasive structure-an analogue in the moral and legal domain of what Noam Chomsky has called the "deep structure" or "universal grammar" of language.7 This structure arises from the fact that morality and law engage psychological adaptations with the same natural function: to allow us to resolve various classes of social contract problems8 flexibly. Drawing on and extending a number of contemporary insights from evolutionary psychology and evolutionary game theory, this Article develops the claim that we resolve these problems by employing a particular class of psychological attitudes, which are neither simply belief-like states nor simply desire-like states, though they bear affinities to both. The attitudes will be called "obligata," as later explained.9 As they appear in us, they are a peculiar blend of prepositional attitudes,10 deontological motivations to follow rules, and reciprocally conditioned expectations of and attitudes toward other persons. Obligata are also judgment-sensitive attitudes-in the sense that reasons can be sensibly asked or offered for the judgments we express with them"-and they are bound up with a number of motives and familiar moral emotions, like shame and guilt.12 They are the attitudes we express when we engage in moral and legal discussion. Obligata constitute our sense of obligation and thereby breathe life into our moral and legal practices. Their structure is the deep structure of law and morality. An understanding of obligata will, moreover, have important consequences not only for legal theory but also for how we should approach normative proposals in law. There is a well-developed and long-standing strain of scholarly literature-predominantly arising in the law and economics movement-that either explicitly or implicitly presupposes a very different psychological picture of us as acting primarily on the basis of separable beliefs about the world and self-interested desires (or preferences) for various states of affairs.13 On this common view, our practical reasoning is purely instrumental and self-interested, and proponents of this view sometimes claim that we only have individual reasons to pursue things like our considered preferences. More recently, a number of researchers have begun to document numerous ways that we deviate from this so-called Homo economicus model and have made efforts to accommodate the fact that we sometimes exhibit desires that are altruistic or other-regarding.14 Behavioral economists have similarly begun to recognize the degree to which we employ a number of so-called "heuristics" and "biases" in our practical reasoning, and therefore approximate ideal instrumental reasoning only imperfectly. …