Public Reason Research Paper

1. The Diversity Of Reason

1.1 The Enlightenment

Before considering different conceptions of public reason, it is important to grasp what the very idea of public reason presupposes. According to the conception of reasoning that dominated the European Enlightenment of the seventeenth and eighteenth centuries, reason is inherently universal, and so shared and public. On this Enlightenment conception, reason is a shared capacity of all human beings, and norms of good reasoning are universal. Any premise p that is true for one person is necessarily true for all others; if the inferential rule ‘(p • (p → q)) → q’ is valid for one person, it is necessarily valid for all. The true and valid results of one person’s reasoning are thus necessarily true and valid for all. According to this standard Enlightenment view, the use of common human reason not only produces consensus on scientific beliefs, it also leads to convergence of moral and political opinions. To be sure, people might disagree on matters of science or ethics, but that would be due to mistaken beliefs or irrationality: some have arrived at the wrong answer. The process of Enlightenment was the only remedy for this—the increasingly better use of reason to uncover truths about the natural and the social world. The ideal or model was that of Newtonian physics: just as our common reason had uncovered the laws of matter and motion, so too could it be expected to uncover the laws of human nature, society, morals, and politics. Each field was awaiting its Newton.

1.2 Relativism And Social Science

It is a familiar story how the systematic study of cultures with radically different norms from those of Europe gave rise to cultural relativism. When confronted with the very different mores of the Zuni and Kwakiutl Indians and Dobu Islanders of Papua New Guinea, Ruth Benedict (1934) endorsed a relativistic view—their norms were justified for them, just as Western norms were for Europeans. As anthropologists began to study non-European cultures in more depth, and became increasingly more sophisticated and self-reflective in their techniques, disputes arose about the proper method for anthropologists to interpret the belief systems of other cultures. For example, was a belief in magic or a deity to be understood as simply a false belief on which the ‘natives’ relied? John Stuart Mill (1974 [1843], pp. 766–7) believed that an investigator could best under- stand the magical beliefs of other cultures by attributing to them erroneous beliefs and invalid inferential rules. Others, adopting a principle of charity, have insisted that the best interpretation of a culture minimizes the number of false beliefs attributed to its members (Davidson 1973). Thus the best interpretation—which makes sense of the ‘native’s’ meta- physical theories, religious convictions, and their beliefs about nature—might seek to show that a belief in spirits is, after all, rational given their world view. Thus the second step in the relativist attack on the Enlightenment’s ideal of reason was to endorse relativism concerning what beliefs are rational in different cultures. The last step in the relativistic project is to apply tolerance to the idea of reason itself. Can Western anthropologists properly interpret other cultures if they apply their Western conception of reason in their interpretation? Is the very idea of reason culturally relative?

Independently, psychological studies of human reasoning led to doubts about whether everyone shares the same norms of reasoning. The work of, among others, Richard Nisbett, Lee Ross, Paul Slovic, and Amos Tversky showed that normal adults often do not employ the norms of reasoning long advocated by philosophers as correct. For example, many normal adults adhere to the ‘gambler’s fallacy.’ According to standard probability theory, the odds of independent events occurring do not depend on whether that type of event has occurred in the past: if the odds of a ‘six’ being rolled by a fair dice is one-in-six, this probability in no way depends on whether no sixes have been rolled or all sixes have been rolled in the past. Yet many normal reasoners believe that, after a long run of sixes, the odds of another six are less than one-in-six, or if none recently have been rolled, many are convinced that a six is ‘due.’ Based on a variety of studies of such ordinary reasoners, some philosophers advocate ‘normative cognitive pluralism.’ According to Stephen Stitch, ‘Normative cognitive pluralism is not a claim about the cognitive processes people do use; rather it is a claim about good processes—the cognitive processes that people ought to use. What it asserts is that there is no unique system of cognitive processes that people should use, because various systems of cognitive processes that are very different from each other are equally good’ (1990, p. 13).

1.3 Pluralism And Indeterminancy

Social science thus provided one source of the ‘fragmentation of reason.’ Of course there was, and still is, lively debate within social scientific and philosophical circles about whether any such relativistic view of reasoning is justified, and if so to what extent individuals employ different, but equally good, norms of reasoning. Nevertheless, some form of cognitive relativism is widely accepted. Concurrently, developments in the philosophy of science were challenging the idea of common, human, reasoning in the very citadel of the Enlightenment—science itself. Whatever doubts may be entertained about the application of Western reason to other cultures, or departures from expert norms by ordinary reasoners, surely science is still the model of rational discourse tending to convergence of opinion leading to the truth. To many, Thomas Kuhn’s analysis of scientific practice demonstrated that, rather than a shared project of pursuit of the truth, judged by rules of reason held by all, scientific inquiry takes place within ‘paradigms’ that determine not only what constitutes research problems but what constitutes success in a research program. Within a group of scholars sharing a paradigm the Enlightenment’s ideal of common norms of reason and consensus on the truth will be approximated; and insofar as ‘normal science’ is dominated by a single paradigm in each field, there often is a common mode of reasoning. But in times of scientific crisis, when paradigms compete, some have insisted that there is no rational, impartial way to adjudicate among the competing theories.

The crux of Kuhn’s analysis is that because data underdetermines theories, scientists draw on values in adjudicating among theories. ‘To a greater extent than other sorts of components of the disciplinary matrix,’ writes Kuhn, ‘values may be shared by men who differ in their application. Judgments of accuracy are relatively, though not entirely, stable from one time to another and from one member to another in a particular group. But judgments of simplicity, consistency, plausibility, and so on often vary greatly from individual to individual … Even more important, in those situations where values must be applied, different values, taken alone, would often dictate different choices. One theory may be more accurate but less consistent or plausible than another’ (Kuhn 1970, p. 185). The crucial claim is that there is no uniquely rational way to order these various desiderata—simplicity, consistency, plausibility—and different orderings endorse different scientific theories upholding competing truth claims. Equally well-informed scientists employing their reasoning in perfectly legitimate ways can arrive at different judgments about what is true. Fred D’Agostino has generalized the analysis. In any field of inquiry, when there exists both a plurality of criteria and no impartial way to order the criteria, the criteria are apt to be indeterminate in their application. Different orderings produce different outcomes—reasons for belief. According to D’Agostino, the criteria only yield a determinate result when an ordering is provided, but impartial reason cannot give us that. Much of postmodernism is based on this key idea. Reason is inherently perspectival because of the inherent plurality of relevant considerations for which there is no rational, impartial ranking.

1.4 Reasonable Pluralism

Kuhn’s analysis of scientific practice and D’Agostino’s generalization rely on the idea of indeterminancy: reason undetermines choice between various theories and perspectives. A more modest view maintains that our powers of reasoning are inconclusive on many complex matters of science, morality, and politics. Claim C is characterized by reasonable pluralism if some perfectly reasonable agents do, while others do not, have good reasons for accepting C. For a controversy to be characterized by reasonable pluralism it is not simply the case that people actually disagree about the merits of C, but that it is reasonable for one person to assert C and another not-C. This is a far less radical claim than was examined in the last section: it is not argued that the question ‘C or not-C?’ is inherently indeterminate but only that present beliefs about C are inconclusively justified. According to John Rawls, our disputes about value seem subject to reasonable disagreement because our understanding of what is good and valuable is especially subject to what he has called the ‘burdens of judgment.’ According to Rawls, reasonable judgments so often are at odds because:

(a) the evidence is often conflicting and difficult to evaluate;

(b) (as in Kuhn’s example) even when we agree on the relevant considerations, we often weigh them differently;

(c) because our concepts are vague, we must rely on interpretations that are often controversial;

(d) the manner in which we evaluate evidence and rank considerations seems to some extent the function of our total life experiences, which of course differ;

(e) because different sides of an issue rely on different types of normative considerations, it is often hard to assess their relative merits;

(f ) in conflicts between values, there often seems to be no uniquely correct answer (Rawls 1993, p. 57).

Because these matters are so complex and uncertain, different people will reach different, competing, credible, or reasonable conclusions. In the face of complexity, our powers of reasoning do not produce convergence.

2. Conceptions Of Public Reason

2.1 Public Rationality And Public Reasons

Important movements in social science, the philosophy of science, and moral and political philosophy thus have combined to cast grave doubt on the Enlightenment’s confidence that the free exercise of human reason leads us to agree. In the face of these challenges to the ideal of common human reason, theories of distinctly public reason have been advanced to show how people can share reasons (Korsgaard 1996, Chap. 10). However, this idea is ambiguous. It may constitute a response to relativistic social science (Sect.1.2), which challenges the very idea of a shared conception of human reason. Understood thus, the ideal of public reason is an ideal of public rationality, or a shared conception of rationality. The challenge posed by reasonable pluralism (Sect. 1.4) is more modest. Advocates of reasonable pluralism maintain that even if we apply shared standards of reason, our deliberations will not yield shared reasons for belief. In a weaker sense, then, the ideal of public reason is an ideal of public reasons, or how we can arrive at shared reasons to believe and act. A theory of public reason may advance a theory of public rationality and/or public reasons.

Three main conceptions of public reason stand out: (a) the epistemic, (b) the consensual, and (c) the political.

2.2 Epistemic Theories Of Public Reason

In philosophy, ‘epistemology’ refers to the theory of knowledge or, more broadly, the theory of justified belief. Epistemic theories of public rationality, then, maintain that at least some common norms of reasoning can be justified to everyone. The Enlightenment view was that all valid norms of reasoning can be justified to everyone—reason was inherently public. Epistemic theories of public rationality need not, however, advance such a sweeping claim. Importantly, an epistemic theory of public rationality may adopt a modest version of the ‘relativism of reasons’ (Sect. 1.2), according to which in some cases person Alpha may have a fully justified norm of reasoning N while Beta accepts a fully justified norm of reasoning M, where it is the case that N and M are inconsistent. In cases where only N and M are relevant to deliberation, a relativism of rationality will manifest itself; Alpha may have reasons based on N that Beta will deny on the basis of M, and both will be justified. However, to establish a thoroughgoing relativism of reasoning that undermines the possibility of public reason, it is not enough to establish that this can sometimes occur; it must be shown that no common norms of rationality can be justified to all—that it is always (or at least usually) the case that for any justified norm of reasoning held by Alpha, some person Beta will be justified in accepting a competing norm. That is the sweeping relativistic claim rejected by epistemic theories of public rationality (Gaus 1996).

Advocates of epistemic public rationality can reply to both the anthropological argument for the relativism of reasons, and psychological studies uncovering the diversity of norms employed in reasoning (Sect. 1.2). In reply to the anthropological argument, advocates of public reason can embrace Martin Hollis’ view that an anthropologist must build up an interpretation of an alien language by locating a ‘bridgehead.’ The assumption underlying the bridgehead strategy is that others generally perceive what we perceive and tend to say about it the sorts of things we would say. Relying on these assumptions, the anthropologist begins by translating everyday, basic perceptual sentences such as ‘Yes, this is a brown cow’ and ‘No, it is not raining right now.’ Now, Hollis insists, this bridgehead not only includes translations of such basic beliefs, but basic logical rules, since ‘what a sentence means depends on how the beliefs which they express are connected, and that to justify a claim to have identified a belief one must show the belief is connected to others.’ Consequently, in the main, the logic employed by those in different cultures must either be very similar to our own or unintelligible. Axioms such as ‘p → p’‘ ~ (p • ~ p)’ and ‘(p • (p → q)) → q’ are more than simply our norms of reasoning. They are constituents of any system that we can identify as a way of reasoning (Hollis 1970a, pp. 214–15, 1970b, p. 232.) If ‘natives’ reason logically at all, then they reason as we do. The point, then, is that the context that sets the stage for the possibility of relativism—that we confront others, different from us but of whom we can make some sense—presupposes widespread shared norms of inference as well as beliefs. Thus the very possibility of mutual intelligibility sets a limit on the extent to which we can understand others as employing cognitive processes different from our own.

In reply to psychological studies showing the diversity of norms employed by normal reasoners, advocates of public reason can rely on evidence supporting the hypothesis that people employ a mental logic—a system of mental inference rules—in their actual reasoning. Indeed, most psychologists studying actual reasoning suppose some version of the mental logic theory. To be sure, mental logic may depart from the standard propositional calculus. Psychologists studying English reasoners, for instance, have found that English speakers do not interpret connectives in a way consistent with standard logic. Particularly troubling are interpretations of ‘if, then’ statements (as well as ‘or’ connectives), which are not typically used in ways that correspond to standard analyses in logic. In response to these findings, psychologists such as Lance J. Rips and Martin D. Braine have developed sets of natural inferential rules that correspond to the way in which speakers of English employ connectives. Rips has gone beyond this to develop rules modeling causal reasoning as well.

Mental logic views strongly incline toward the hypothesis that these logics are in some way natural or innate, though to precisely what extent is open to investigation. There may well be a complicated interplay between language and logic, such that English speakers tend to employ some inferential rules not utilized by others. A plausible hypothesis is that the capacity to develop a mental logic is innate, though the precise developmental path taken depends on a variety of factors, including one’s native language. If so, however, this is sufficient to undermine the plausibility of a radical relativism of norms of rationality. The set of possible mental logics—laws governing thought—is apt to be pretty severely constrained.

2.3 Consensus Theories Of Public Reason

Epistemic accounts of public reason uphold our ability to reason together because they insist that we do, indeed must, share basic rules of inference. In contrast, consensual accounts of public reason conceive it as arising out of a shared social life and/or shared discourse. A number of otherwise diverse philosophers such as Ludwig Wittgenstein, Jurgen Habermas, Richard Rorty, Susan Hurley, and Philip Pettit all point to the idea that reasoning is a social phenomenon. In order to be a deliberator, one must be a member of a community in which one’s beliefs and rules are intelligible to others. One comes to understand what is a justified or unjustified belief, and what is a good or a bad way of reasoning, by sharing the norms and standards of communities, including communities of inquirers. Thus some insist that ‘ultimately, there is only one criterion by which beliefs can be judged valid, and that is that they are based on agreement reached by argumentation’—we converge on them (this is Habermas’s 1991, p. 14 gloss on Rorty’s ‘particular version of discourse theory’). Habermas draws an intimate connection between mutual understanding (Verstandingung) and agreement (Einverstandnis). It would seem that to understand others we must in some way arrive at intersubjective agreement about norms of rationality and good reasons. Consequently, the phrase of ‘public reason’ becomes almost redundant: something can only be identified as reason because it is the object of public, interpersonal, agreement.

Wittgenstein and his contemporary followers such as Hurley (1989) and Pettit (1993) suggest a broadly similar view. Reasoning itself presupposes a ‘community’—common rules of thought. Wittgenstein (1958) argued that one could not have a private rule that one only followed once—for in such a case we could not know whether the rule was actually followed. More generally, it has been argued that one cannot have a purely private rule, for one needs to be able to distinguish when one has correctly followed the rule and when one has gotten it wrong. But, assert Wittgensteinians, the difference between correct and incorrect application of a rule cannot be located in individual belief systems, but only by the individual comparing her application of the rule to those of her fellows: each must look to others to check and correct her rule-based performances. Since thinking is necessarily rule driven, the analysis applies to reason itself. Thus it seems that the very idea of rule-following— and, so, of reasoning—supposes convergence with others. If so, the search for reason is a search for consensus.

In one respect this view, somewhat surprisingly perhaps, returns to the basic idea of the Enlightenment—all reason is public reason. But whereas the Enlightenment was confident in asserting this because of the widespread faith in a universal, common, human faculty of reason that could accurately represent reality, consensual theorists see reason as arising out of a shared public life. To put it crudely, rather than reason producing consensus, consensus generates reason. Thus the publicness of such reason, unlike that of the Enlightenment’s, is consistent with a cultural relativistic conception of rationality. The public, intersubjective agreement, reached by one culture—which is constitutive of their very conception of rationality—may be very different from that upheld by another.

Because consensual accounts of public reason stress the constitutive nature of public consensus to the very idea of reason, and because public consensus may be promoted by political institutions, more radical consensual theorists such as D’Agostino give political institutions a constitutive role in determining what reason is (1996, Chap. 9). This is a radical view indeed—however, it is not entirely novel, perhaps going back as far as Hobbes. For Hobbes ([1651] 1948), the conflict in the state of nature arises from conflicting private judgments; people’s private reasoning yields conflicting judgments of right and wrong, as well as matters of fact, and this leads to the less intellectual conflict that characterizes the state of nature. Hobbes’s solution is to appoint an ‘arbitrator.’ This ‘judge,’ says Hobbes, provides ‘public reason’ to which private reason ‘must submit.’ The arbitrator proclaims what each has reason to do, and so defines a single, coherent conception of reason. Because, in Hobbes’ view, we have authorized the judge (i.e., sovereign) to define public reason for us, the sovereign’s pronouncements constitute a shared public reason on which there is consensus.

2.4 Public Reason qua Political Reason

D’Agostino’s radical view allows the political to shape the rational. A more modest proposal with which this radical view is easily confused maintains that the notion of public reason is a purely political idea, in the sense that it concerns only how we reason together about politics. This understanding of public reasons lies at the heart of what is commonly known as ‘political liberalism.’

Rawls’s political liberalism is a response to the problem posed by reasonable pluralism (Sect. 1.4). For Rawls the crucial problem is that citizens in democratic societies entertain a plurality of what he calls reasonable ‘comprehensive doctrines’—overall philosophies of life centered on religious, philosophical, or moral beliefs. This pluralism seems a permanent feature of modern societies. ‘Political liberalism assumes that, for political purposes, a plurality of reasonable yet incompatible comprehensive doctrines is the normal result of the exercise of human reason within the framework of free institutions of a constitutional regime’ (Rawls 1993, p. xvi). The reasonable pluralism of comprehensive views renders such views unacceptable as bases for the justification of political power. Rawls endorses the ‘liberal principle of legitimacy,’ i.e., that ‘our exercise of political power is fully proper only when it is exercised in accordance with a constitution the essentials of which all citizens as free and equal may be reasonably expected to endorse in the light of principles and ideals acceptable to their common human reason’ (p. 137). Thus, because there exists a reasonable plurality of comprehensive doctrines, basing the justification of political power on any of them violates the liberal principle of legitimacy. This leads Rawls to seek a political conception that ‘all affirm’ and that is ‘shared by everyone.’ Such a conception would be supported by the diverse reasonable comprehensive doctrines that characterize our democratic societies. It would generate public reasons that would fit into our many reasonable, but irreconcilable, comprehensive views. Some version of the principle of political legitimacy motivates the search for public reasons in contemporary liberal political philosophy: if the exercise of coercive political power relies on nonpublic reasoning, it is oppressive and illegitimate in relation to those who do not share those reasons.

Rawls’s core argument—and so his entire political liberalism—apparently depends on the contrast between comprehensive views and the shared, political, conception. Whereas comprehensive conceptions produce diverse reasons that conflict, the political point of view provides public reasons—reasons that all reasonable comprehensive views can endorse.

Habermas (1995) suggests that Rawls posits an ‘a priori’ distinction between the political and nonpolitical spheres. At least at times Rawls seems to suggest that the political point of view can be conceptually distinguished from moral, religious, and philosophical matters; whereas the former identifies a common point of view that can be affirmed by all, when human reason is applied to moral, religious, and philosophical issues it leads to reasonable disagreement. It is difficult, however, to accept the claim that some single conception of the political is shared by all reasonable persons in modern democratic societies. Political theorists have often pointed to the ‘political’ as an ‘essentially contested’ concept—one that is open to divergent, reasonable, interpretations (Connolly 1983, Chap. 1). If citizens of modern democratic societies disagree about the concept of the political, it cannot serve the function of identifying public reasons that overcome reasonable pluralism. Like the moral and philosophical, the nature of the political itself seems a matter of reasonable disagreement.

An alternative interpretation of Rawls’ view is to take the political conception as constructed out of that which is shared. On this reading the nonpolitical is, by definition, those matters on which the free use of reason by citizens in democratic societies leads to different, reasonable conclusions. It is, by its very nature, the realm of reasonable pluralism. In contrast, one might define the political as those matters on which reason converges in democratic societies, and so necessarily generates constitutional principles that satisfy the principle of liberal legitimacy. The political is thus characterized as the overlapping consensus of those diverse comprehensive views characterizing modern societies. The problem for this interpretation is that Rawls himself indicates that the free use of human reason leads us to reasonable disagreement about conceptions of justice and constitutional essentials. The ‘political’ qua ‘shared perspective’ is limited to the abstract concept of a ‘liberal political order’ (Rawls 1993, p. 241). ‘By this [Rawls says] I mean three things: first, it specifies certain basic rights, liberties, and opportunities (of the kind familiar from constitutional democratic regimes); second, it assigns a special priority to these rights, liberties and opportunities, especially with respect to claims of the general good and of perfectionist values; and third, it affirms measures assuring all citizens’ adequate all-purpose means to make effective use of their basic liberties and opportunities’ (p. 223). Thus stated, the content of public reason seems sparse indeed. Unfortunately, if a more detailed articulation of this idea is provided, Rawls indicates that the use of human reason again leads to disagreement. Apparently modern democratic societies agree on only the most abstract of public— political—reasons.

3. Conclusion: Reasoning In A Plural Society

Puzzles about the possibility of shared, public rationality and reasons derive from a variety of sources: social science, the philosophy of science, and the moral pluralism of modern societies. Although developments in all these fields serve to cast doubt on the Enlightenment’s ideal of a common universal reason, they pose different challenges. The findings of anthropology call into question universal norms of rationality; psychology questions whether so-called universal norms are actually employed in human reasoning. Kuhnian philosophy of science suggests an irremediable indeterminancy of the application of our general standards, even in science itself. Worries about reasonable pluralism focus on the possibility of shared moral and political norms in societies that disagree deeply on questions of value and the nature of the good life.

Just as the challenges arise from multiple sources, so do theories of public reason. Epistemic theories dispute that modern social science casts serious doubt on the necessity of shared norms of rationality in the interpretation of other cultures and in individual deliberation. Although some divergence in justified norms of reasoning no doubt occurs—and can be made sense of—radical divergence is implausible. Consensus theories of public reason maintain that to make sense to each other we must think alike—we must employ common rules of thought. The application of such common rules, say neo-Wittgensteinians, only makes sense in the context of shared social practices. Reason arises out of shared social life; reason is inherently public because it is necessarily a product of social consensus. Finally, political liberalism seeks to establish that, amid the diversity of moral and philosophical views that characterize modern societies, a common political point of view can generate shared public reasons to regulate coercion.

The ideal of public reason, then, is as diverse as the sources of our doubts about the possibility of shared ways of reasoning in contemporary societies. In all its manifestations, however, the ideal of public reason seeks to maintain the heritage of the Enlightenment—the free use of human reason will lead us to converge on the best justified beliefs.

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