Argument from Queerness

1. Introduction

The Argument from Queerness is a family of metaethical arguments that challenge the existence of objective moral values by claiming that, if such values existed, they would be metaphysically and epistemologically “queer” in an objectionable sense. The term “queer” is used in its older philosophical sense, meaning strange, unusual, or ontologically suspect, rather than as a social or identity label.

In its canonical formulation by J. L. Mackie, the argument has two main components:

• a metaphysical claim that objective moral properties would have to be intrinsically prescriptive or reason-giving in a way unlike any familiar natural property; and
• an epistemological claim that knowing such properties would require a special, sui generis moral faculty.

Proponents maintain that this combination makes robust moral realism—the view that there are stance-independent moral facts—costly or implausible, especially in a broadly naturalistic worldview. They typically suggest that we can explain our moral practices by appealing instead to psychological, social, or evolutionary factors, without positing objectively prescriptive values.

Critics, by contrast, argue that the alleged “queerness” is overstated, that other accepted entities (such as mathematical or normative facts about rationality) are equally “queer,” or that moral properties can be understood in less mysterious terms, whether as natural or non-natural properties. The argument has therefore become a central point of dispute among moral realists, error theorists, expressivists, and other metaethicists.

This entry examines the argument’s origins, structure, and subsequent developments, as well as major responses and its influence on contemporary metaethics.

2. Origin and Attribution

The Argument from Queerness is principally associated with John Leslie Mackie (1917–1981), an Australian-born philosopher who worked mainly in the analytic tradition. Its canonical statement appears in his book:

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“If there were objective values, then they would be entities or qualities or relations of a very strange sort, utterly different from anything else in the universe.”

— J. L. Mackie, Ethics: Inventing Right and Wrong (1977)

Mackie’s First Formulation

In Ethics: Inventing Right and Wrong, Mackie introduces the Argument from Queerness in the context of defending moral error theory. The argument appears in Chapter 1 (“The Subjectivity of Values”), where Mackie distinguishes between:

• metaphysical queerness, concerning the nature of putative objective values; and
• epistemological queerness, concerning how we could come to know them.

He attributes the conclusion that there are no objective moral values to the combined force of these two queerness considerations, together with the availability of debunking explanations of moral practice.

Precedents and Influences

Although the label “Argument from Queerness” is Mackie’s, commentators trace thematic precedents to:

Mackie’s argument is thus generally treated in the literature as a distinctive, named component of his error-theoretic project, even though its concerns echo earlier worries about moral ontology and epistemology.

Subsequent Naming and Usage

Later metaethicists—both sympathetic and critical—adopted Mackie’s phrase “Argument from Queerness” as a standard label. It now functions as a term of art in discussions of:

• objections to robust moral realism, especially non-naturalist versions; and
• more general worries about normativity and its place in a naturalistic picture of reality.

While variants and extensions exist, the argument is typically attributed directly to Mackie’s 1977 treatment.

3. Historical and Intellectual Context

The Argument from Queerness emerged within a specific mid–20th-century analytic context shaped by debates over naturalism, non-naturalism, and the status of normative discourse.

Post-Positivist Analytic Ethics

In the decades preceding Mackie’s Ethics (1977), moral philosophy had moved beyond logical positivism, which had often dismissed ethical statements as non-cognitive. Figures such as G. E. Moore, W. D. Ross, and C. D. Broad had defended forms of intuitionist non-naturalist realism, positing sui generis moral properties known by rational intuition. Mackie’s queerness argument directly targets this tradition, questioning both the alleged properties and the intuitionist epistemology.

At the same time, new naturalist moral realist theories were developing, attempting to align moral facts with empirical or broadly scientific views of the world. Philosophers were also refining non-cognitivist and emotivist views (e.g., A. J. Ayer, R. M. Hare), which treated moral judgments as expressions of attitudes rather than descriptions of facts.

Growing Naturalism and Scientific Worldview

The latter half of the 20th century saw an increasingly confident scientific naturalism in philosophy:

• Metaphysically, there was reluctance to postulate entities that did not fit within a broadly scientific ontology.
• Epistemologically, there was skepticism toward special cognitive faculties not continuous with perception, inference, or empirical inquiry.

Mackie’s queerness argument reflects these attitudes. It presses the thought that intrinsically prescriptive properties and sui generis moral intuitions sit uneasily within this naturalistic framework.

Relation to Earlier Skepticism

Mackie’s project also inherits earlier skeptical strands:

While Mackie does not simply repeat these earlier views, his argument is often interpreted as articulating, in contemporary analytic terms, a historically recurring tension between robust objective values and a naturalistic understanding of the world.

4. The Argument from Queerness Stated

Mackie’s Argument from Queerness is commonly reconstructed as an inductive or abductive argument against the existence of objective moral values. It emphasizes both the alleged strangeness of such values and the availability of alternative explanations of moral practice.

Core Claims

A standard schematic formulation is:

1. If there were objective moral values, they would have to be intrinsically prescriptive or categorically reason-giving in a way unlike any familiar natural property (metaphysical queerness).
2. If such values existed, we would require a special, sui generis moral faculty or mode of access to know them (epistemological queerness).
3. Within a broadly naturalistic worldview, we have reason to be suspicious of positing such queer properties and faculties, especially when they are not needed to explain our moral practices (queerness principle).
4. Our moral judgments and practices can instead be explained by psychological, evolutionary, and social mechanisms that do not posit objective moral values (debunking alternative).
5. Therefore, we have strong reason to deny that objective moral values exist; our moral discourse involves a systematic error (error-theoretic conclusion).

Metaphysical and Epistemological Components

Mackie separates his discussion into:

• a metaphysical strand, challenging the idea of sui generis, intrinsically action-guiding entities or properties; and
• an epistemological strand, challenging the plausibility of special moral intuitions or perceptions that would track those properties.

Both strands are intended to support a general methodological stance: other things being equal, one ought not to postulate ontologically or epistemologically “queer” items when more ordinary explanations suffice.

Variants and Extensions

Later philosophers have:

• reconstructed the argument as a form of argument from explanatory dispensability, emphasizing parsimony;
• extended queerness worries to other normative domains (e.g., reasons for belief) to test the argument’s reach;
• or restricted its target to specific forms of robust non-naturalist moral realism, leaving open more modest realist or constructivist views.

Despite such variations, most treatments preserve the dual focus on the alleged strangeness of robust moral properties and the supposed oddity of epistemic access to them.

5. Metaphysical Queerness: Strange Moral Properties

The metaphysical component of the Argument from Queerness concerns the nature of putative objective moral properties. Mackie claims that, to play the role many moral realists assign to them, these properties would have to be “of a very strange sort” compared with familiar natural or descriptive properties.

Intrinsic Prescriptivity

Central to Mackie’s concern is intrinsic prescriptivity: the idea that some properties are not merely descriptive but contain built-in requirements or reasons for action simply in virtue of what they are. On many realist views, a property like wrongness or goodness:

• does not just describe an action;
• also demands that agents refrain from or pursue that action, regardless of their desires or aims.

Mackie suggests that such intrinsically reason-giving properties are metaphysically unusual. They apparently “magnetize” behavior, linking facts about what is the case with categorical requirements about what ought to be done.

Comparison with Familiar Properties

To highlight the alleged queerness, Mackie contrasts moral properties with more ordinary ones:

Proponents of the queerness argument contend that no other widely accepted properties combine objectivity, irreducibility, and intrinsic prescriptivity in this way.

Targets within Moral Realism

Metaphysical queerness is often seen as particularly pressing for:

• non-naturalist moral realists, who treat moral properties as sui generis and irreducible;
• any view that insists moral properties provide categorical reasons independent of agents’ desires or practical identities.

Some naturalist moral realists attempt to avoid the queerness charge by identifying moral properties with complex natural properties (e.g., promoting well-being), thus denying that there are additional, irreducible prescriptive properties. Non-naturalists, by contrast, may accept sui generis normativity but deny that its distinctiveness renders it objectionably queer. The metaphysical queerness discussion thus focuses on whether robustly normative properties can be accommodated within a plausible overall ontology.

6. Epistemological Queerness: Strange Moral Knowledge

The epistemological strand of the Argument from Queerness concerns how, if objective moral properties existed, humans could reliably know them. Mackie argues that any plausible account of such knowledge would require positing an unusual cognitive faculty.

The Need for a Special Moral Faculty

On many forms of moral realism—especially non-naturalist versions—moral properties are:

• not directly observable in the way physical properties are; and
• not straightforwardly derivable from non-moral facts via ordinary empirical or logical inference.

To explain how we might know that, say, cruelty is wrong in an objective, stance-independent way, realists commonly appeal to:

• rational intuition,
• a kind of moral perception or sensitivity, or
• a distinctive capacity for practical reason that discerns reasons or requirements.

Mackie characterizes these proposals as invoking a special “faculty of moral perception or intuition” and contends that such a faculty is epistemologically “queer” within a naturalistic picture of human cognition.

Contrast with Ordinary Epistemic Methods

The queerness claim is sharpened by comparison with standard sources of knowledge:

Proponents of the queerness argument maintain that adding a special moral faculty complicates our epistemology without independent justification beyond the assumption that robust moral truths exist.

Alternative Views

Responses to epistemological queerness differ:

• Some non-naturalist realists accept a basic faculty of moral intuition or rational reflection and argue that not all fundamental epistemic capacities (e.g., logical insight) are empirically grounded.
• Naturalist realists often claim that moral knowledge is continuous with empirical and practical reasoning, reducing the need for a sui generis faculty.
• Anti-realists may embrace Mackie’s worry, using it to support skeptical or error-theoretic positions.

The epistemological queerness discussion thus centers on whether plausible, non-mysterious accounts of moral knowledge are available, and what their availability or absence implies for moral realism.

7. Logical Structure and Form of the Argument

The Argument from Queerness is usually understood as neither a strict deductive proof nor a simple appeal to intuition, but as an inductive or inference-to-the-best-explanation argument. It combines considerations of metaphysical and epistemological queerness with a parsimony-based preference for non-queer explanations of moral phenomena.

Standard Reconstruction

A common reconstruction distinguishes explicit and implicit premises:

1. Conditionals about queerness

   • If objective moral values exist, there must be metaphysically queer properties (intrinsically prescriptive, categorically reason-giving).
   • If such values exist, there must be epistemologically queer faculties (special moral intuitions or perceptions).

2. Methodological premise

   • One should avoid positing ontologically and epistemologically queer entities and faculties when adequate non-queer explanations are available (explanatory parsimony).

3. Debunking premise

   • Our moral beliefs and practices can be satisfactorily explained by non-moral, naturalistic factors (e.g., evolutionary, psychological, sociological).

4. Conclusion

   • Therefore, we have strong reason to reject the existence of objective moral values; our moral discourse is systematically in error.

The argument is defeasible: it aims to shift the balance of theoretical reason against moral realism rather than to establish its falsity with logical necessity.

Inductive and Abductive Features

The argument’s form is often described as:

• Inductive, because it generalizes from the absence of accepted queer entities in successful theories to skepticism about additional queer items;
• Abductive, because it compares competing explanations of moral practice and concludes that an anti-realist or debunking account is explanatorily preferable and more parsimonious.

Internal Structure: Two Subarguments

Some commentators separate the overall argument into two related subarguments:

Both are then combined with the parsimony and debunking premises to support an error-theoretic or broadly anti-realist stance.

Debate in the literature often concerns whether these premises are themselves defensible, whether parsimony should carry the weight Mackie assigns it, and whether realist theories can undercut the queerness claims by offering less exotic accounts of moral properties and knowledge.

8. Role in Mackie’s Moral Error Theory

In Ethics: Inventing Right and Wrong, Mackie deploys the Argument from Queerness as one of the central supports for his moral error theory—the view that moral judgments aim at stating objective truths but systematically fail because there are no such truths.

Position within Mackie’s Overall Strategy

Mackie’s broader project combines:

• a semantic claim: ordinary moral discourse is cognitivist; it purports to describe objective values;
• an ontological claim: there are in fact no objective moral values;
• an explanatory claim: we can explain moral practices without positing such values.

Within this framework, the Argument from Queerness provides a key rationale for the ontological denial: moral properties would be too strange to credibly exist, given our best overall picture of the world.

Interaction with Other Arguments

Mackie also offers other considerations, including arguments from relativity (moral disagreement) and from the function of moral language. The queerness argument plays a distinctive role:

Together, these strands aim to make error theory more attractive than realism by presenting realism as both ontologically and epistemologically costly and explanatorily unnecessary.

Error Theory as a Systematic Conclusion

On Mackie’s view, the upshot is not that moral discourse is meaningless, but that its assertoric content is uniformly false when it purports to assert objective moral facts. The Argument from Queerness helps justify this sweeping negative claim by arguing that the sort of objective values moral discourse presupposes would be metaphysically and epistemologically queer enough that we have reason to believe they do not exist.

Subsequent error theorists, such as Richard Joyce, often cite Mackie’s queerness considerations as a foundational motivation for developing more detailed error-theoretic and fictionalist accounts of moral discourse and practice.

9. Naturalist Realist Responses

Naturalist moral realists accept objective moral truths but seek to understand them in terms continuous with natural or scientifically respectable properties. They often respond to the Argument from Queerness by challenging its metaphysical and epistemological premises and by reinterpreting moral properties to avoid queerness.

Reducing or Identifying Moral Properties with Natural Properties

Naturalist realists such as Richard Boyd and Peter Railton argue that moral properties can be:

• identified with or realized by complex natural properties (e.g., promoting human flourishing, satisfying rational desires under ideal conditions); or
• understood as higher-order properties that supervene on non-moral, natural facts without introducing independent, non-natural entities.

On such views:

• Moral properties are not sui generis, non-natural items;
• They enter into causal and explanatory relations in familiar ways;
• They are knowable using methods continuous with empirical inquiry and practical reasoning.

This is intended to undercut the metaphysical queerness premise by denying that moral properties must be ontologically exotic.

Epistemic Continuity with the Sciences

Naturalist realists also reject the need for a sui generis moral faculty. Instead, they propose that moral knowledge arises from:

• empirical investigation (psychology, social science, biology);
• reflection on human interests, flourishing, and social practices;
• processes akin to reflective equilibrium, integrating moral intuitions with theoretical considerations.

This picture aims to make moral epistemology less “queer” by assimilating it to broader patterns of inquiry and rational deliberation.

Explanatory and Practical Roles

Many naturalist realists turn the queerness challenge into an opportunity to stress the explanatory role of moral facts:

By embedding moral properties within the causal-explanatory fabric of the natural world, naturalist realists contend that the queerness label no longer aptly applies.

Diversity among Naturalist Views

Different naturalist programs—e.g., Cornell realism, Railton’s sophisticated consequentialism, and various functional or response-dependent accounts—offer distinct ways of cashing out these commitments. What they share, in responding to Mackie, is the attempt to show that one can be a moral realist while avoiding the metaphysical and epistemological oddities that the Argument from Queerness highlights.

10. Non-Naturalist Realist Responses

Non-naturalist moral realists accept that moral properties are not reducible to natural properties, but they deny that this irreducibility makes such properties objectionably “queer.” Their responses typically challenge Mackie’s standards for metaphysical and epistemological acceptability.

Accepting Sui Generis Normativity

Philosophers such as Derek Parfit and Russ Shafer-Landau explicitly embrace moral and normative properties as sui generis. They argue that:

• Some aspects of reality (e.g., normative reasons, moral requirements) are fundamental;
• Not all fundamental facts need to resemble physical or psychological facts;
• Distinctiveness does not entail illegitimacy.

From this perspective, the queerness label reflects an unwarrantedly restrictive naturalist metaphysics rather than a genuine defect in non-natural moral properties.

Parallels with Other Abstract or Normative Domains

Non-naturalists often draw analogies to other apparently non-natural realms:

An influential line of response holds that if Mackie’s queerness concerns undermine moral facts, they may equally threaten these other normative or abstract facts. Non-naturalists sometimes embrace a unified picture of normativity that includes both moral and epistemic reasons, resisting any selective skepticism.

Moral Epistemology without Mystery

Non-naturalist realists also respond to epistemological queerness. They often defend:

• rational intuition or a priori reflection as basic epistemic sources, analogous to our grasp of logical or mathematical truths;
• the idea that awareness of normative reasons can arise through reflective judgment, not via a mysterious sixth sense.

On this view, acknowledging a basic capacity to apprehend normative truths is no more problematic than acknowledging basic logical or mathematical insight.

Refinements and Constraints

To alleviate queerness worries, some non-naturalists place constraints on their metaethical theories, for example:

• insisting that normative truths supervene on non-normative truths, preserving a tight connection between the normative and the descriptive;
• emphasizing that moral knowledge is fallible and theory-laden, integrating moral intuitions with systematic reflection.

These refinements aim to show that non-naturalist realism can be both robustly realist and methodologically respectable, resisting the charge that it postulates inexplicable metaphysical or epistemological posits.

11. Objections and Critiques of Queerness

Critics of the Argument from Queerness target its premises, its scope, and its underlying methodological assumptions. Several prominent lines of objection have emerged.

Overstated Queerness

Some philosophers contend that Mackie exaggerates how strange moral properties and moral knowledge would be. They argue that:

• Irreducible properties or basic normative facts are not automatically suspect;
• Many accepted entities (e.g., mathematical objects, modal facts) are also “unusual” without being rejected.

On this view, the argument’s force depends on an arguably contentious preference for a narrowly naturalistic ontology.

Parity with Other Normative Facts

Another influential objection notes that Mackie’s queerness concerns seem to apply not just to moral facts but to normative facts in general, including:

• reasons for belief,
• standards of rationality,
• epistemic justification.

Critics such as Thomas Nagel and David Enoch suggest that:

• if we accept normative reasons for belief, then we already accept some normative “queer” facts;
• eliminating all such facts would undermine rational discourse itself;
• so the argument either overreaches (leading to implausible global normative skepticism) or must be restricted in ways that weaken its impact on morality specifically.

Explanatory Role and Indispensability

Some moral realists argue that, contra Mackie, moral facts have explanatory power:

If moral facts play an indispensable explanatory role, critics argue, then parsimony-based objections lose much of their force. The queerness of moral properties, if any, may then be an acceptable cost, analogous to accepting unobservable particles in science.

Methodological and Burden-of-Proof Concerns

Some philosophers question the methodological premise that queerness (understood as metaphysical or epistemological distinctiveness) counts strongly against a posit. They raise issues such as:

• Whether the burden of proof lies with realists to show that moral properties are not queer, or with anti-realists to show that their queerness is intolerable;
• Whether arguments from queerness illicitly conflate unfamiliarity with implausibility;
• Whether intuitive discomfort with non-natural normativity should carry significant evidential weight.

These critiques suggest that the Argument from Queerness may rest on contestable methodological norms rather than neutral philosophical ground.

Internal Tensions and Reformulations

Some commentators also explore whether Mackie’s argument applies equally to constructivist or response-dependent accounts, or whether it primarily targets a specific brand of robust realism. This has led to reformulations that narrow or clarify the queerness charge, and to debates about whether the argument can be reconstructed in a way that is both precise and compelling without becoming self-undermining or trivial.

12. Implications for Moral Epistemology

The Argument from Queerness has significant implications for moral epistemology, the study of how, if at all, we can know moral truths. By challenging the plausibility of both objective moral properties and special moral faculties, it pressures theories about the sources and justification of moral belief.

Skeptical and Error-Theoretic Implications

If one accepts both:

• that robust objective moral properties would require a special faculty to know them, and
• that positing such a faculty is unwarranted,

then it appears difficult to vindicate knowledge of robust moral truths. This supports forms of:

• moral skepticism (doubting that we know moral truths), or
• moral error theory (denying that the moral propositions we accept are true).

In this way, queerness arguments feed into more general worries about whether moral beliefs can be justified in a way comparable to scientific or everyday beliefs.

Pressure on Intuitionism

The epistemological queerness strand directly targets moral intuitionism, which maintains that moral truths are known via intuition or rational insight. The challenge is that:

• if such intuitions are understood as deliverances of a sui generis faculty, they look epistemologically queer;
• if they are instead assimilated to general rational reflection, intuitionism may need to revise its self-understanding, emphasizing inferential and justificatory structures continuous with other domains.

Some intuitionists respond by likening moral intuition to our grasp of logical or mathematical truths, thereby attempting to mitigate queerness concerns.

Shaping Naturalist Moral Epistemology

For naturalist realists, queerness arguments motivate the search for accounts of moral knowledge that rely on:

• empirical evidence (e.g., about human flourishing, social institutions),
• broadly rational deliberation about means and ends,
• coherence-based methods such as reflective equilibrium.

These approaches aim to show that moral epistemology can be continuous with other forms of inquiry, without invoking mysterious faculties.

Influence on Anti-Realist Epistemic Projects

Non-cognitivists, expressivists, and quasi-realists often accept that there is no special moral epistemology tracking robust moral facts. Instead, they reconceive:

• justification in moral discourse as a matter of coherence, responsiveness to reasons internal to practices, or improved coordination;
• disagreement as conflict of attitudes rather than competition over objective facts.

From this perspective, queerness considerations help motivate a shift from questions of moral truth to questions about practical reasoning, endorsement, and attitude revision.

Overall, the Argument from Queerness functions as a critical test for moral epistemologies: any account that relies on robust objective values or sui generis faculties must explain why such commitments are not objectionably queer, while alternative accounts may attempt to explain moral thought and talk without them.

13. Connections to Evolutionary and Debunking Arguments

The Argument from Queerness is closely related to, and often combined with, evolutionary and other debunking arguments about the origins of moral belief. While distinct, these lines of thought mutually reinforce each other in many anti-realist and skeptical frameworks.

Debunking Structure and Queerness

A debunking explanation aims to account for a set of beliefs by appealing to causal origins that make no reference to their truth. In the case of morality, evolutionary and cultural explanations suggest that:

• moral dispositions and judgments enhanced cooperation, group cohesion, or reproductive fitness;
• these processes shaped our moral psychology independently of any tracking of objective moral facts.

The queerness argument complements this by adding that, even if such objective facts existed, they would be metaphysically and epistemologically unusual. Together, the two lines of thought suggest that:

1. We do not need robust moral facts to explain our moral beliefs (debunking).
2. The kinds of facts that realists postulate would be ontologically and epistemically suspect (queerness).

Evolutionary Explanations

Evolutionary accounts, developed by figures such as Michael Ruse and later Richard Joyce, emphasize that:

• cooperative and altruistic tendencies may have been selected for;
• moral norms and emotions (e.g., guilt, indignation) can be understood as adaptive mechanisms.

These explanations can be presented in a table alongside queerness considerations:

By offering a complete naturalistic story of why we have moral beliefs, evolutionary debunking can make the postulation of queer moral properties seem superfluous.

Distinguishing but Integrating the Arguments

Philosophers sometimes stress that:

• the queerness argument is primarily about the nature and epistemic accessibility of moral facts;
• evolutionary debunking arguments are primarily about the genealogy and justification of moral beliefs.

Nonetheless, the two can be integrated:

• Queerness sets up a prima facie skepticism about robust moral entities;
• Debunking explanations provide an alternative story that makes skepticism more compelling by showing how our beliefs could have arisen and persisted without truth-tracking.

Realists responding to these combined pressures may:

• argue that evolutionary processes could still be truth-sensitive under certain conditions;
• or contend that evolutionary explanations do not undercut our entitlement to moral beliefs if those beliefs are also supported by independent rational reflection.

14. Influence on Non-Cognitivism and Quasi-Realism

The Argument from Queerness has significantly influenced the development of non-cognitivist and quasi-realist metaethical theories, which seek to capture the practical and expressive roles of moral discourse without positing robustly queer moral properties or faculties.

Resonance with Non-Cognitivism

Non-cognitivists (e.g., A. J. Ayer, R. M. Hare) already held that moral judgments primarily express attitudes or prescriptions rather than describe objective facts. Queerness considerations:

• support the idea that robust moral facts are metaphysically and epistemologically problematic;
• encourage the re-interpretation of moral statements as expressions of approval/disapproval, commitments, or plans, rather than factual claims.

In this way, the Argument from Queerness lends argumentative backing to the non-cognitivist’s decision to avoid robust moral ontology.

Quasi-Realism’s Strategic Use of Queerness

Simon Blackburn’s quasi-realism explicitly engages with queerness worries. Quasi-realists:

• accept an expressivist semantics (moral utterances express attitudes);
• aim to “earn the right” to talk of truth, objectivity, and facts in a deflationary or projectivist sense.

Queerness plays a role by:

• motivating the rejection of independent, stance-independent moral facts;
• reinforcing the view that moral discourse’s apparent realism should be explained via our practices of projection, endorsement, and normative commitment, rather than by positing queer moral properties.

Blackburn and others present quasi-realism as a way to have much of what moral realists want in terms of discourse and practice while avoiding the metaphysical costs highlighted by Mackie.

Shaping Expressivist Accounts of Normativity

Later expressivists, such as Allan Gibbard, also engage with queerness arguments. Gibbard’s norm-expressivism, for instance, treats moral judgments as expressions of acceptance of norms. Queerness considerations underpin:

• the decision not to ground normativity in sui generis moral facts;
• the emphasis on planning, coordination, and dispute resolution as the core functions of moral language.

By explaining normativity in terms of practical attitudes and social practices, expressivists aim to diffuse the need for a mysterious link between descriptive facts and categorical prescriptions.

Influence on Hybrid and Deflationary Views

Queerness arguments have also inspired hybrid and deflationary accounts that:

• retain a thin notion of moral truth (e.g., minimal truth-aptness);
• but reject any commitment to robustly queer moral properties.

These theories often see themselves as occupying a middle ground: they accept that moral discourse has truth-conditions in some sense, yet they interpret those conditions in ways that avoid Mackie’s metaphysical and epistemological worries.

Overall, the Argument from Queerness has been a key factor in pushing non-cognitivist and quasi-realist theories to develop more sophisticated accounts of how moral language can function and seem objective without invoking objectionable queerness.

15. Status in Contemporary Metaethics

In contemporary metaethics, the Argument from Queerness remains both influential and controversial. It is widely discussed, but there is no consensus on its ultimate probative force.

Continuing Centrality

The argument is often treated as a standard challenge that any robust form of moral realism must address. Contemporary textbooks and articles typically:

• present it alongside other major arguments (from disagreement, supervenience, and explanatory power);
• use it to frame debates about naturalism vs. non-naturalism and realism vs. anti-realism.

Many metaethical theories are at least partially shaped by how they respond to or accommodate queerness considerations.

Divergent Assessments

Philosophers disagree sharply about the argument’s weight:

This diversity reflects deeper disagreements about naturalism, the nature of normativity, and appropriate methodological constraints in metaphysics and epistemology.

Refinements and Reformulations

Recent work has refined the queerness discussion by:

• distinguishing more carefully between different kinds of normativity (moral vs. epistemic);
• questioning whether intrinsic prescriptivity is indeed built into ordinary moral thought;
• developing more nuanced accounts of moral perception, intuition, and rational reflection.

Some philosophers argue that, once clarified, the argument targets only a subset of realist theories, leaving room for more modest or “relaxed” forms of realism.

Broader Theoretical Implications

The argument has also contributed to:

• increased scrutiny of metanormative assumptions;
• cross-domain comparisons between morality, rationality, and other normative areas;
• a more explicit articulation of what it would mean for normative properties to be “part of” the natural world.

Even where philosophers reject Mackie’s conclusions, the queerness framework has become a touchstone for evaluating the metaphysical and epistemological commitments of metaethical theories.

Overall, the Argument from Queerness continues to function less as a settled refutation of moral realism and more as an enduring pressure point around which metaethical positions define and justify themselves.

16. Legacy and Historical Significance

The Argument from Queerness has left a lasting mark on metaethics and on analytic philosophy more broadly, shaping both the development of moral skepticism and the articulation of realist and anti-realist positions.

Consolidating Moral Error Theory

Historically, Mackie’s deployment of the argument helped establish moral error theory as a distinctive and serious metaethical option. Subsequent error theorists, including Richard Joyce and others, have:

• refined the queerness considerations;
• combined them with evolutionary and cultural debunking arguments;
• developed sophisticated accounts of how moral practice might continue under the recognition that its realist presuppositions are false.

In this way, queerness has become one of the canonical motivations for systematic moral skepticism.

Structuring Debates about Naturalism and Normativity

The argument has also played a significant role in clarifying the stakes of naturalism in metaethics:

By pressing the question of how normativity fits into a naturalistic worldview, the queerness argument has spurred extensive work on the metaphysics of reasons, value, and rationality.

Stimulating Alternative Metaethical Theories

The queerness challenge has:

• encouraged naturalist realists to develop richer accounts of moral properties and their epistemic accessibility;
• pushed non-naturalist realists to defend more explicit metaphysical and epistemological commitments;
• motivated non-cognitivist, expressivist, and quasi-realist theories that aim to preserve the practical significance and apparent objectivity of moral discourse without positing queer entities.

As a result, much contemporary metaethics can be read as a series of responses to Mackie’s challenge, either by embracing its skeptical thrust or by attempting to neutralize it.

Influence Beyond Metaethics

Finally, the queerness framework has influenced discussions in:

• general normativity, regarding epistemic and practical reasons;
• philosophy of mind, especially concerning motivational states and reason-responsiveness;
• philosophy of science, where analogies with explanatory indispensability and parsimony are explored.

Its historical significance lies not only in the specific conclusion Mackie draws but also in the way the argument has reshaped the agenda: any comprehensive theory of morality is now expected to address, explicitly, how it avoids or accommodates the alleged metaphysical and epistemological queerness of robust moral facts.