In This Article Expand or collapse the "in this article" section Moral Epistemology

  • Introduction
  • General Overviews
  • Anthologies
  • Encyclopedia Entries
  • Historically Important Accounts
  • Rationalist Accounts of Moral Knowledge
  • Empiricist Accounts of Moral Knowledge
  • Psychological Theories of Moral Judgment
  • Psychological Theories of Moral Development
  • Moral Belief and Evolution
  • Moral Skepticism
  • Moral Nihilism
  • Moral Disagreement
  • Intuitions about Cases
  • Intuitions about Principles
  • Moral Perception
  • Desires as Intuitions of Value or Reasons
  • Emotions and Moral Judgment
  • Inferring “Ought” from “Is”
  • Moral Knowledge from Inference to the Best Explanation
  • Coherence Theories of Moral Knowledge and Warrant
  • Moral Contextualism
  • The Reliability of Pre-theoretical Moral Judgment
  • The Possibility of Theoretical Moral Knowledge
  • Reflective Equilibrium
  • Moral Expertise and Deference
  • Feminist Approaches to Moral Epistemology
  • Moral Skill or Know-How
  • Moral and Mathematical Knowledge
  • Decision under Moral Uncertainty
  • Non-cognitivism and Moral Epistemology

Philosophy Moral Epistemology
Aaron Zimmerman
  • LAST REVIEWED: 26 August 2014
  • LAST MODIFIED: 26 August 2014
  • DOI: 10.1093/obo/9780195396577-0208


Moral epistemology is the study of moral knowledge and related phenomena. The recorded history of work in the field extends (at least) 2,500 years to Socrates’s inquiries into whether virtue and expertise in governance can be taught. Every major moral theorist since then has advanced theses about the possibility of moral knowledge and those modes of thinking, feeling, and reasoning that are most conducive to improvements in moral outlook. Though the study of moral language and the metaphysics of morality received more attention by Western philosophers in the 20th century, interest in moral epistemology has grown in recent years as theorists have turned to advances in the scientific study of moral development and moral judgment—and their origins in biological and cultural evolution—in the hopes of shedding new light on the old questions. By further understanding the processes that give rise to our moral beliefs, and the critical evaluation and consequent evolution of moral frameworks, we hope to gain further insight into what distinguishes those rational, reasonable, or well-considered moral views that would seem to comprise moral knowledge from those irrational, false, or unduly biased judgments that fall short. This article begins by describing general overviews of moral epistemology, moves on to consider historically important accounts of moral knowledge, and then addresses contemporary scientific accounts of moral judgment, moral development, and the foundations of moral response in our evolved biology. With these elements in place, it moves on to moral skepticism and the question of whether we have any moral knowledge; moral nihilism, or the view that there are no moral truths to be known; and the extent and nature of fundamental moral disagreement: perhaps the most common route to skepticism about morality. The “special” topics that follow these core concerns demonstrate the breadth and richness of the field. We would seem to have “intuitions” of the morality of certain actions, people, or institutions. Some (non-skeptical) theorists liken these intuitions to perceptions of color or beauty. Others argue that desires provide non-inferential knowledge of value, that basic moral principles are self-evident, or that we can directly infer “ought” from “is.” Theorists discuss, among other things, the reliability of ordinary processes of moral judgment, the role of coherence and reflection in augmenting the rationality of folk moral views, the possibility of theoretical moral knowledge akin to scientific knowledge, and the rationality of basing one’s moral views on testimony.

General Overviews

Brink 1989 and Timmons 1998 distinguish metaethics from other forms of inquiry into morality and moral epistemology from other areas of metaethics. Arrington 1989 traces the recent history of moral epistemology from the “non-cognitivist” accounts of Stevenson and Hare to the rationalism of Nagel, the realism of McDowell, and the relativism of Harman. Audi 1999 distinguishes four approaches: empiricism, rationalism, intuitionism, and non-cognitivism. Utilitarian empiricism claims the intrinsic goodness of something can be inferred from its being desired by people for its own sake and equates the rightness of an act with its promoting intrinsic goodness so understood. Kantian rationalism identifies right actions with those performed from maxims that pass a test of universalizability, the validity of which is known in an a priori, non-inferential manner. Intuitionism holds that a variety of principles are self-evident: Those who understand them are justified in believing them (on the basis of that understanding) in a manner sufficient for knowledge. Non-cognitivism might be thought to imply epistemological moral skepticism, but there are norms we employ to assess feelings and commitments, so a non-cognitivist might construct a substantive moral epistemology. Enoch 2011 briefly surveys various skeptical challenges to realist conceptions of morality and argues that they are inessential because, “There is no distinctive epistemology of moral belief” (p. 154, n. 6). The true challenge is to explain the correlation between considered moral judgments and the judgment-independent facts that make them true. The last three chapters of Shafer-Landau 2003 and its defense of moral realism are similarly devoted to epistemological matters. According to Shafer-Landau, moral skepticism is self-undermining because it is a philosophical thesis, and if there is insufficient evidence to support our basic moral beliefs there is insufficient evidence to support any philosophical view. Sinnott-Armstrong 2008 and Zimmerman 2010 are two recent book-length treatments of moral epistemology. Sinnott-Armstrong 2008 ultimately endorses moral contrastivism: if nihilism is not ruled out via fiat we cannot have moral knowledge. But we can know that certain actions are immoral and others moral relative to the assumption that nihilism is false. Zimmerman 2010 finds all arguments for moral skepticism wanting. One can come to know that a particular act of villainy was immoral by directly inferring as much from one’s knowledge of its value-neutral properties. Knowledge of the general principles that underwrite these inferences can be acquired with the aid of imagination and normal affective experience.

  • Arrington, Robert L. Rationalism, Realism and Relativism: Perspectives in Contemporary Moral Epistemology. Ithaca, NY: Cornell University Press, 1989.

    Arrington documents the rise and fall of non-cognitivist theories of morality and evaluates the forms of cognitivism that have been formulated in their wake. In the final chapter, Arrington defends “conceptual relativism.” The rules that constitute our morality cannot be justified, but they do not need to be. They and their correlative ends are simply what we mean by “morality.”

  • Audi, Robert. “Moral Knowledge and Ethical Pluralism.” In The Blackwell Guide to Epistemology. Edited by John Greco and Ernest Sosa, 271–302. Oxford: Blackwell, 1999.

    In the first half of his essay, Audi distinguishes four approaches to moral epistemology: empiricism, rationalism, intuitionism, and non-cognitivism. In the essay’s second half, Audi further describes intuitionism, distinguishes several subspecies of the view, and argues in favor of a “moderate” form, which countenances both inferential and non-inferential knowledge of common sense moral principles and both inferential and non-inferential knowledge of the moral properties of particular actions.

  • Brink, David. Moral Realism and the Foundations of Ethics. Cambridge, UK: Cambridge University Press, 1989, chapter 1.

    DOI: 10.1017/CBO9780511624612

    Brink provides a brief summary of the history of analytic metaethics that distinguishes the epistemological questions involved in this area of inquiry from those of a more metaphysical, semantic, and (purely) psychological nature.

  • Enoch, David. “Epistemology.” In Taking Morality Seriously. By David Enoch, 151–184. Oxford: Oxford University Press, 2011.

    DOI: 10.1093/acprof:oso/9780199579969.003.0007

    Enoch argues that “there is no distinctive epistemology of moral belief.” Moral realists must simply explain the correlation between our core moral beliefs and the moral facts. Enoch’s explanation rests on the assumption that our survival and reproduction (or various factors that promote such survival, e.g., well-being and reciprocated trust) are themselves good.

  • Shafer-Landau, Russ. Moral Realism: A Defense. New York: Oxford University Press, 2003.

    DOI: 10.1093/0199259755.001.0001

    Chapters 10–12 are devoted to epistemological issues. We cannot impugn nihilism on grounds acceptable to a nihilist, but if this entails skepticism, it does so whether or not we adopt a realist conception of moral facts. Skepticism is self-undermining and the process that leads an agent from knowledge of the facts to a judgment of what she ought to do often generates knowledge because of its reliability.

  • Sinnott-Armstrong, Walter. Moral Skepticisms. New York: Oxford University Press, 2008.

    Sinnott-Armstrong surveys a wide range of skeptical positions and positive accounts of moral knowledge. He ultimately endorses a form of “moral contrastivism.” If nihilism is not ruled out via fiat we cannot have knowledge of any positive moral proposition. But we can know that certain actions are immoral and others moral relative to the assumption that nihilism is false.

  • Timmons, Mark. “Metaethics and Methodology.” In Morality without Foundations. By Mark Timmons, 9–31. New York: Oxford University Press, 1998.

    Timmons distinguishes metaethics from normative ethics and differentiates the epistemological component of metaethics from its semantic and ontological elements. He then tries to motivate his commitment to methodological and ontological naturalism and to situate various metaethical positions (and their constituent epistemologies) in relation to this commitment.

  • Zimmerman, Aaron. Moral Epistemology. New York: Routledge, 2010.

    Zimmerman discusses a number of arguments for moral skepticism and a variety of non-skeptical accounts of moral knowledge, dividing the latter into rationalist and empiricist camps. According to Zimmerman, one can directly infer “ought” from “is” without the aid of intuitions or cognitive “seemings.” Knowledge of the general principles that underwrite these inferences or verify their reliability can then be acquired with the aid of imagination and affective experience.

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