Reflective Equilibrium

Reflective equilibrium is a philosophical method and state of coherence among a set of beliefs, achieved through a process of deliberative mutual adjustment between general principles and particular judgements. Rather than beginning from fixed axioms, the method involves revising and refining beliefs at multiple levels until they form a stable, non-contradictory, and practically useful system. Reflective equilibrium has become especially influential in moral and political philosophy, where it is most closely associated with the work of John Rawls, although its methodological roots can be traced to earlier developments in logic and epistemology.

Background and conceptual foundations

The core idea of reflective equilibrium is that justification arises not from a single foundational belief, but from the overall fit between different elements of a belief system. These elements typically include intuitive judgements about particular cases, more general moral or theoretical principles, and background assumptions drawn from broader philosophical or scientific theories. A belief system is in reflective equilibrium when its components support one another in a way that is internally coherent and resistant to further counterexamples or conflicts.
Although the term reflective equilibrium was not originally used, the basic method was introduced by the philosopher Nelson Goodman in his work on the justification of inductive logic. Goodman argued that rules of induction and particular inductive inferences are justified by being brought into mutual agreement through a process of revision and adjustment. This approach later became known as Goodman’s method, and it laid the groundwork for the more explicitly moral and political uses of reflective equilibrium developed by Rawls.

Rawls and the development of the method

The term reflective equilibrium was coined and popularised by John Rawls, most notably in A Theory of Justice. Rawls presented the method as a way of determining and justifying principles of justice by appealing to the human sense of justice, understood as a moral capacity that generates both moral judgements and moral motivation.
In Rawls’s account, the process begins with considered judgements. These are moral judgements made under favourable conditions for reflection, such as freedom from coercion, sufficient information, and careful deliberation. Considered judgements may concern either specific cases or general moral principles at varying levels of abstraction. When inconsistencies arise among these judgements, the agent revises some beliefs—whether particular judgements, general principles, or background assumptions—until a coherent set emerges.
Rawls emphasised that this process is not mechanical. There is no algorithm for deciding which beliefs should be revised. Instead, deliberation involves weighing plausibility, coherence, and practical implications. A set of beliefs in ideal reflective equilibrium is one that would result from this process under conditions of full information and careful reasoning.

Illustrative example of reflective equilibrium

A commonly used type of example involves conflicts between general principles and specific moral judgements. Suppose an individual holds the general principle that one must always obey the commands found in a sacred text. At the same time, the individual judges that it is morally wrong to punish people severely merely for holding certain religious beliefs. If the sacred text appears to command such punishment, the individual faces an inconsistency.
Several routes towards reflective equilibrium are possible. The individual might revise the general principle, for example by restricting obedience to a subset of core teachings. Alternatively, the individual might reinterpret the text, appeal to contextual or historical considerations, or give priority to other moral teachings that mitigate or override the apparent command. Less commonly, the individual might revise the particular judgement and accept the punishment as morally justified. Whatever the outcome, the individual moves towards equilibrium by adjusting beliefs until they no longer conflict and can jointly guide action.

Misinterpretations and clarifications

A number of philosophers have argued that reflective equilibrium is frequently misunderstood. In particular, it has been pointed out that the method should not be reduced to a simple balancing of opposing considerations. Common misinterpretations include:

• Treating reflective equilibrium as merely balancing theoretical accounts against intuitive convictions.
• Describing it as balancing general principles against particular judgements in a purely mechanical way.
• Portraying it as a compromise between opposing ethical theories or divergent moral statements.

Such interpretations risk undermining the cogency of the method by ignoring its emphasis on systematic coherence and justification, rather than compromise or aggregation.

Role in Rawls’s political theory

Reflective equilibrium plays a central justificatory role in Rawls’s political philosophy. One influential interpretation, associated with philosophers such as Norman Daniels and T. M. Scanlon, holds that reflective equilibrium embodies a form of coherentism in moral epistemology. On this view, moral beliefs are justified by their place within a coherent system rather than by appeal to self-evident moral truths.
However, Rawls also suggested a different understanding of the method’s role. In several writings, he argued that his theory of justice does not aim to resolve traditional metaethical debates about moral truth or knowledge. Instead, it serves a practical function: identifying principles of justice that can organise social life in a stable and publicly acceptable way.
From this perspective, reflective equilibrium links the cognitive and motivational aspects of the sense of justice. Principles of justice are justified not only because they cohere with our moral judgements, but because they are capable of being stably endorsed and complied with by members of society. Stability is a crucial criterion: a society governed by principles that its members cannot accept or sustain would be inherently fragile.

Stability and the original position

Rawls argued that candidate principles of justice must demonstrate stability under conditions of reasonable pluralism. Reflective equilibrium contributes to this aim by ensuring that principles are grounded in moral capacities that people actually possess. As part of this project, Rawls applied the method to the idea of a hypothetical original position, in which rational agents choose principles of justice from behind a veil of ignorance, unaware of their own social position, talents, or advantages.
Through reflective equilibrium, Rawls concluded that the principles chosen under these conditions would best capture the underlying sense of justice shared by free and equal citizens. The method is not static: Rawls allowed for provisional fixed points, recognising that equilibrium may shift as individuals consider new cases, arguments, or empirical information.

Wide reflective equilibrium

An important extension of the method is wide reflective equilibrium, a concept also introduced by Rawls and later elaborated by Norman Daniels. Wide reflective equilibrium seeks coherence among three interconnected sets of beliefs:

• Considered moral judgements, including intuitions about particular cases.
• Moral principles, which systematise and explain these judgements.
• Background theories, including relevant scientific, social, and philosophical theories.

By incorporating background theories, wide reflective equilibrium aims to avoid parochialism and to ensure that moral reasoning is informed by the best available knowledge about human psychology, social institutions, and the natural world.

Relation to constructivism

Reflective equilibrium is often associated with constructivist approaches in moral philosophy. The philosopher Kai Nielsen argued that defenders of reflective equilibrium are committed to a form of constructivism, insofar as moral principles are constructed through rational deliberation rather than discovered as pre-existing moral facts. Nielsen rejected the view that reflective equilibrium presupposes a fully coherent set of moral beliefs prior to reflection, instead emphasising the dynamic and revisable nature of moral reasoning.

Criticism and alternative approaches

Despite its influence, reflective equilibrium has been subject to significant criticism. Paul Thagard described the method as a potential smokescreen for a sophisticated form of logical and methodological relativism. He argued that excessive reliance on intuition can entrench existing biases and lead to stable but suboptimal moral frameworks.
Thagard proposed an alternative, more explicitly consequentialist method for justifying norms. This approach involves identifying a domain of practices, specifying candidate norms, determining the goals of those practices, and evaluating how well different norms promote those goals. Norms are then adopted based on their effectiveness rather than their coherence with prior intuitions.