Moral Rationalism and Constructivism

Grounding the authority of moral requirements in practical reason or in the constitution of rational agency.

Definition

Moral rationalism holds that moral requirements are categorical requirements of practical reason; metaethical constructivism is the view that moral facts or truths are not discovered as mind-independent objects but constituted by the deliverances of an idealized procedure of practical reasoning or rational willing.

Scope

This topic covers moral rationalism — the view that moral requirements are requirements of reason that bind agents as such — and metaethical constructivism, which holds that moral truths are constituted by what would be agreed to or willed from a suitably specified standpoint of practical reasoning. It centers on Korsgaard's Kantian constructivism and source-of-normativity question and on Rawls's Kantian constructivism, and contrasts constructivism with both robust realism and antirealism.

Core questions

• Can the authority of morality be derived from the nature of rational agency?
• Are moral truths constructed by a procedure of practical reasoning rather than found?
• How does constructivism differ from both realism and antirealism?
• What grounds the normativity of the principles an agent must will?

Key concepts

• practical reason
• self-legislation
• practical identity
• the constructivist procedure
• categorical requirements

Key theories

Kantian constructivism (Korsgaard)

Normativity arises from the agent's reflective self-constitution: to act at all is to legislate principles for oneself, and the demands of practical identity and humanity yield genuine moral obligations.

Rawlsian constructivism

Principles of justice are constructed as the objects of agreement among suitably situated rational agents, so their objectivity consists in being the upshot of a reasonable procedure rather than tracking prior moral facts.

History

Drawing on Kant's idea of autonomy as self-legislation, Rawls's 'Kantian Constructivism in Moral Theory' (1980) reframed objectivity in ethics procedurally. Korsgaard's The Sources of Normativity (1996) and Self-Constitution (2009) developed a more thoroughgoing metaethical constructivism that grounds normativity in the constitutive features of agency.

Debates

Does constructivism avoid both realism and antirealism?

Constructivists claim a third way between mind-independent moral facts and mere projection; critics argue it either presupposes prior normative truths (collapsing toward realism) or cannot explain bindingness (collapsing toward antirealism).

The bootstrapping worry

Opponents charge that deriving substantive obligations from the bare concept of agency illicitly smuggles in normative content; constructivists reply that constitutive standards of action are genuinely normative for agents.

Key figures

• Christine Korsgaard
• John Rawls
• Immanuel Kant

Seminal works

• rawls1980
• korsgaard1996
• korsgaard2009

Frequently asked questions

Is constructivism a form of moral realism?

It is contested. Constructivists hold moral truths are mind-dependent in that they are constituted by ideal practical reasoning, which sets them apart from robust realism; but they also claim a kind of objectivity that distinguishes them from expressivism and error theory.