Can we know what is right? A philosophical inquiry into ethical knowledge

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1. Introduction

Human beings constantly make judgments about what is right and wrong. Individuals decide whether an action is fair, whether a promise ought to be kept, whether a policy is just, whether an institution has acted responsibly, or whether a particular decision is morally permissible. Such judgments are not confined to philosophical debate. They arise in everyday life and in professional decision-making, including questions concerning the allocation of resources, financial integrity, educational fairness, organisational responsibility and the treatment of other persons. Yet a significant philosophical question lies beneath these ordinary judgments: how do we know that what we judge to be right actually is right?

This question changes the nature of the inquiry. It is one thing to ask what constitutes a morally good action; it is another to ask what would justify our belief that an action is morally good. The first is primarily a question of normative ethics. The second is an epistemological question concerning the possibility, sources, and justification of moral knowledge. Moral epistemology is centrally concerned with precisely this problem: whether and how human beings can possess justified beliefs or knowledge about moral matters (Lemos, 2009; Stanford Encyclopedia of Philosophy, 2024) [9, 16]. The distinction is important because people may hold ethical beliefs for very different reasons. A person may believe that corruption is wrong because this was taught in childhood, because it violates a professional rule, because it harms other people, because it violates human dignity, or because it conflicts with a principle the person regards as universally binding. These reasons are not epistemically equivalent. The mere existence of a reason is therefore insufficient; the philosophical question is whether the reason provides adequate justification for the moral conclusion. The problem becomes more difficult when reasonable people disagree about moral questions. Moral disagreement exists within and across societies and has long been used as an argument against the possibility of objective moral knowledge (Stanford Encyclopedia of Philosophy, 2026) [17]. However, disagreement alone does not establish that there is no moral truth. People also disagree about empirical matters, and disagreement may result from differences in evidence, interpretation, background assumptions, interests, or reasoning. Contemporary discussions of moral disagreement consequently ask a more demanding question: whether the particular character and persistence of moral disagreement provide a reason to doubt that moral judgments can track objective moral truths (Cosker-Rowland, 2017; Rini, 2026) [4, 14]. This article therefore asks:

To What Extent Can Ethical Judgments About What Is Right or Wrong Be Regarded as Knowledge? The objective is to critically examine the possibility and justification of ethical knowledge.

The article advances a qualified position. Ethical judgments can constitute knowledge, but not simply because they are sincerely believed, widely accepted, or intuitively compelling (on the epistemic role of intuition, see Huemer, 2005; Cowan, 2015) [3]. Their epistemic status depends on the quality of their justification and, where moral truth is assumed to be objective, on whether the judgment is responsive to that truth. At the same time, moral knowledge is not necessarily infallible. Human beings may reason well from incomplete information, misunderstand relevant facts, be influenced by bias, or reasonably disagree about the appropriate moral principle. Ethical knowledge should therefore be understood as fallible knowledge supported by defensible justification, rather than as absolute certainty.

The argument proceeds by first clarifying the relationship between knowledge, belief and justification. It then examines why moral knowledge presents distinctive philosophical difficulties, considers several influential approaches to moral justification, analyses the significance of moral disagreement, and examines the relationship between factual knowledge and normative judgment. The paper concludes by considering the implications of this analysis for professional decision-making without allowing the disciplinary applications to displace the central philosophical question.

2. From Knowledge in General to Ethical Knowledge

2.1. Knowledge, Belief and Justification

Any inquiry into ethical knowledge must begin with a broader epistemological question: What distinguishes Knowledge from Belief?

A person can believe something without knowing it. Beliefs may be based on testimony, perception, memory, inference, intuition, authority or habit. Some beliefs are true, some false, and some may be held with considerable confidence despite weak grounds. Consequently, sincerity or psychological certainty cannot by itself transform belief into knowledge. A traditional starting point in epistemology is the justified-true-belief conception of knowledge: roughly, a person knows a proposition when the proposition is true, the person believes it, and the belief is appropriately justified. Gettier's influential 1963 paper demonstrated that justified true belief is not, by itself, sufficient for knowledge because a person may arrive at a true and justified belief partly through epistemic luck (Gettier, 1963) [5].

This development is important for ethical epistemology. Consider the proposition:

Deliberately falsifying financial information is morally wrong.

A person may believe this because a parent taught it to them. Another may believe it because professional regulations prohibit falsification. A third may believe it because falsification deceives others and undermines trust. A fourth may justify it through a broader principle concerning honesty, respect for persons, or the conditions necessary for fair cooperation.

The proposition is the same, but the epistemic grounds differ. Consequently, the question is not merely whether an ethical proposition is believed. It is whether the belief is appropriately justified and truth-directed.

2.2. Ethical Belief Is Not Automatically Ethical

Knowledge The distinction can be expressed in three stages: Ethical belief: “I believe this action is right.” Ethical judgment: “I judge this action to be right because I have considered relevant reasons, principles, and circumstances.”

Ethical knowledge: “I have adequate epistemic grounds for judging that this action is right, and those grounds are sufficiently defensible to warrant the claim to knowledge.” The third formulation is deliberately cautious. It does not imply that moral knowledge requires absolute certainty. Contemporary epistemology generally recognises that knowledge and justification can be compatible with the possibility of error. Indeed, discussions of moral epistemology explicitly consider whether moral knowledge can be acquired through forms of justification analogous to those employed in other domains of knowledge (Lemos, 2009; Audi, 1997) [2, 9].

The important point is therefore that ethical knowledge requires more than conviction. A person can be morally sincere and nevertheless mistaken.

This distinction also prevents a common philosophical error: treating the intensity of moral conviction as evidence of moral truth. Strong conviction may demonstrate psychological commitment, but it does not by itself establish epistemic warrant.

3. Why Ethical Knowledge Is Philosophically Difficult

Ethical knowledge is difficult not because ethical questions are necessarily meaningless, but because several interconnected problems arise when human beings attempt to justify moral claims.

3.1. The Problem of Moral Objectivity

One central question is whether there are moral truths that exist independently of individual or collective preference. A realist position holds, broadly, that at least some moral claims are objectively true or false (Shafer-Landau, 2023) [15]. On such a view, the statement that an action is wrong is not merely a report about the speaker's feelings or preferences. It purports to make a claim about how things morally are. By contrast, anti-realist positions deny or substantially qualify this conception of moral truth. Some forms of subjectivism relate moral truth to attitudes or standards; non-cognitivist approaches question whether moral utterances function primarily as truth-apt descriptions; and error theory maintains that ordinary moral claims purport to describe objective moral facts that do not exist. These positions therefore differ not simply over which actions are right, but over what moral claims themselves mean and whether there are moral facts to be known (Shafer-Landau, 2023) [15]. This distinction is crucial. If moral claims do not describe any truth-apt reality, then moral knowledge would have to be understood very differently from ordinary factual knowledge. If objective moral facts exist, however, the epistemological task becomes one of explaining how human beings can acquire justified beliefs about them (McGrath, 2023) [10]. Thus, the question “Can we know what is right?” partly depends on the prior question “What kind of thing is moral truth?”

3.2. Moral Disagreement

The existence of extensive moral disagreement presents a second challenge.

People disagree about abortion, punishment, war, distributive justice, euthanasia, animal welfare and numerous other moral questions. They may also disagree about practices that different societies regard as acceptable or unacceptable. Such disagreement has historically been used to support relativist and skeptical conclusions (Stanford Encyclopedia of Philosophy, 2026) [17].

However, the inference from disagreement to impossibility is not straightforward.

Disagreement may result from disagreement about empirical facts. Two people may agree that unnecessary suffering is wrong but disagree about whether a particular policy increases or decreases suffering. Their moral disagreement may therefore partly be an empirical disagreement. Disagreement may also result from different background assumptions, competing moral principles, different interpretations of a situation, self-interest, emotional influences, or differences in the information available to the parties. Contemporary philosophical analysis consequently treats the epistemological significance of disagreement as a substantive question rather than assuming that disagreement itself settles the matter (Cosker-Rowland, 2017) [4]. This does not mean disagreement is philosophically harmless. If two people appear to be equally competent and equally informed and yet reach incompatible moral conclusions after serious reflection, each has reason to examine the confidence of their own judgment. Recent work on moral disagreement continues to explore whether disagreement with an epistemic peer should exert distinctive pressure on moral confidence (Rini, 2026) [14]. Moral disagreement therefore supports epistemic humility, but it does not by itself establish moral scepticism.

4. Competing Approaches to the Justification of Ethical

Judgments If ethical knowledge is possible, the next question is how ethical judgments can be justified. There is no single uncontested answer. Different moral traditions emphasise different sources of justification.

4.1. Reason and Universal Principle: Kant

Kant provides one of the strongest examples of a rationalist approach to moral justification. In the Groundwork of the Metaphysics of Morals, he seeks a supreme principle of morality and develops the categorical imperative as a principle of unconditional moral obligation (Kant, 2012) [8]. For Kant, morality cannot simply depend on contingent desires, consequences or social conventions. Moral requirements must possess a form of universality capable of binding rational agents. His formulations of the categorical imperative therefore provide a test for whether a maxim can be willed as a universal law and whether persons are treated as ends rather than merely as means.

From an epistemological perspective, the importance of Kant is not merely that he proposes particular moral rules. He illustrates an answer to the question of what could justify moral judgment: rational consistency and principles capable of universal justification.

The strength of this approach is that it resists reducing morality to personal preference or expected advantage. However, a difficulty remains. Even if universal principles are accepted, applying them to complex circumstances may require judgments about facts, competing duties and the interpretation of particular cases. Rational principles do not eliminate the need for practical judgment.

4.2. Consequences and Moral Justification

A different approach evaluates actions by their consequences. Utilitarianism, particularly in the tradition associated with Bentham and Mill, assesses conduct according to its contribution to happiness or well-being. Mill's Utilitarianism presents utility or happiness as a criterion for distinguishing right from wrong (Mill, 2015) [11].

The epistemological attraction of consequentialist reasoning is that it appears to connect moral judgment with considerations that can, at least in principle, be investigated. If an action is justified because it prevents substantial harm, evidence about its likely effects becomes relevant to the moral judgment.

Yet this approach also exposes an important limitation: empirical knowledge about consequences does not automatically determine their moral significance. A decision-maker must still justify why the relevant consequences ought to be valued, how different interests should be weighed, and whether certain rights or principles may constrain the pursuit of aggregate welfare.

Consequentialism therefore demonstrates an important feature of ethical knowledge: moral reasoning may depend upon empirical knowledge without being reducible to empirical knowledge.

4.3. Practical Wisdom: Aristotle

Aristotle offers a different conception of ethical rationality. Rather than treating ethical judgment as the mechanical application of universal rules, Aristotle gives a central role to phronesis, commonly translated as practical wisdom (Aristotle, 2002) [1].

Practical wisdom involves the capacity to deliberate well about what should be done in particular circumstances. Aristotle's account recognises that ethical life contains particulars that cannot be fully captured by abstract rules. Practical wisdom is consequently acquired through experience, habituation, deliberation and the development of appropriate dispositions.

This has an important epistemological implication. Knowing a moral principle may not be sufficient for knowing what ought to be done in a particular situation. Ethical knowledge may involve knowing how to judge well, not merely knowing that a principle exists.

Aristotle's position also introduces an important corrective to overly intellectualised accounts of ethical knowledge. Human judgment is situated in concrete circumstances, and good judgment requires sensitivity to relevant particulars. Nevertheless, practical wisdom cannot simply mean “whatever an experienced person feels is right.” Experience itself can be distorted by prejudice, poor habits or defective values. Practical wisdom therefore requires disciplined ethical formation rather than experience alone.

4.4. A Broader Lesson from the Competing Approaches

Kant, consequentialism and Aristotle should not be treated simply as three competing answers from which one must select a winner. Their significance for the present inquiry is epistemological.

They demonstrate three different ways in which ethical judgment may seek justification: ▪ Principle: Is the judgment consistent with a defensible moral principle? ▪ Consequence: Is the judgment supported by what the action is reasonably expected to produce? ▪ Practical judgment: Does the judgment appropriately respond to the morally relevant particulars of the situation?

Each approach also reveals a limitation in the others. Principles may require interpretation; consequences may depend on uncertain predictions; practical judgment may be vulnerable to bias and inconsistency.

This suggests that ethical justification may be more complex than the search for a single decision rule.

5. The Is–Ought Problem: Can Facts Establish Values?

A further difficulty concerns the relationship between factual and normative claims.

Hume (1739–1740/2007) famously drew attention to the transition that moral arguments sometimes make from statements about what is the case to statements about what ought to be the case. His observation has generated extensive philosophical debate, but one enduring lesson is that a normative conclusion cannot simply be assumed to follow from descriptive premises without some additional normative bridge.

1. A particular policy benefits the majority. 2. Therefore, the policy is morally right.

The conclusion does not follow from the first premise alone. An additional normative premise is required, such as: Policies that maximise overall well-being are morally preferable.

Only after that principle is introduced does the argument become a recognisably moral argument.

This distinction matters for ethical knowledge because it prevents empirical evidence from being treated as if it automatically settles normative questions. Suppose evidence establishes that a programme is economically efficient. That may be relevant to judging the programme ethically, but efficiency alone does not determine whether the programme is just. Similarly, evidence that a policy benefits a majority does not, without further argument, establish that the interests of a minority may legitimately be disregarded.

The implication is not that facts are irrelevant to ethics. Quite the opposite: ethical judgments often depend critically on accurate factual knowledge. Rather, facts and values play different epistemic roles.

A defensible ethical judgment therefore requires both adequate attention to relevant facts and explicit examination of the normative principles connecting those facts to the conclusion.

6. Moral Disagreement and the Limits of Ethical

Knowledge The preceding discussion suggests that disagreement should neither be ignored nor exaggerated.

If ethical knowledge were completely independent of reasoning, evidence and argument, disagreement would pose little epistemological difficulty. But if moral judgments claim to be knowledge, disagreement among apparently competent reasoners requires explanation.

One possible response is relativism: moral judgments may be correct relative to particular cultural or social standards. Another response is moral scepticism: persistent disagreement may give us reason to doubt whether moral knowledge is possible. A third response is moral realism: disagreement may reflect human fallibility without eliminating the possibility of objective moral truth. The realist response deserves particular attention because disagreement does not logically entail the absence of truth. The fact that people disagree about a proposition does not establish that the proposition has no correct answer. What disagreement can establish is that the route from human judgment to truth may be less secure than we sometimes assume. The contemporary literature explicitly recognises this distinction: disagreement creates an epistemological challenge for realism, but it does not by itself refute realism (Cosker-Rowland, 2017; McGrath, 2023) [4, 10]. At the same time, it would be too easy simply to explain disagreement away. If a moral theory repeatedly produces disagreement among informed and reflective reasoners, the disagreement may indicate a weakness in the theory, in our epistemic access to moral truth, or in the assumption that moral truth is objective.

The most defensible conclusion is therefore intermediate. Moral disagreement gives us defeasible reason for epistemic caution, but not conclusive grounds for abandoning the possibility of moral knowledge.

This position also explains why ethical knowledge should be regarded as fallible. A person can be justified in believing a moral proposition and nevertheless be mistaken. Knowledge, on this view, does not require immunity from error; rather, it requires that the belief be appropriately grounded rather than merely lucky, arbitrary or unsupported.

7. Toward a Fallibilist Account of Ethical Knowledge

The preceding analysis supports a more precise answer to the paper's central question.

Ethical knowledge should not be understood as possessing unquestionable access to moral truth. Such a standard would make knowledge extraordinarily difficult to establish, not only in ethics but across many areas of human inquiry. At the same time, lowering the standard so far that any sincere moral conviction qualifies as knowledge would collapse the distinction between knowledge and belief. A more defensible position is fallibilism. All knowledge claims could be wrong. We never prove truth; we only fail to disprove it yet. Coined by Charles Sanders Peirce, developed by Karl Popper (Peirce, 1931; Popper, 2002) [12, 13]. On a fallibilist account, a person may know something while remaining capable of error in principle. What matters is not certainty but whether the belief is sufficiently well grounded under appropriate epistemic conditions. Contemporary discussions of epistemic justification similarly recognise that justification need not guarantee truth and that knowledge involves more than merely possessing a true belief (Gettier, 1963; Lemos, 2009) [5, 9].

Applied to ethics, this suggests several conditions for a defensible claim to ethical knowledge.

First, the Judgment Should Be Reason-Responsive The person should be able to provide reasons for the judgment rather than relying solely on assertion, authority or preference.

Second, relevant factual evidence should be considered. Because moral judgments are often about concrete circumstances, ignorance or serious misunderstanding of relevant facts can undermine ethical judgment.

Third, the normative premises should be open to examination.

A moral conclusion cannot be defended adequately if its underlying principle is simply assumed while alternative principles are ignored.

Fourth, the Judgment Should Demonstrate Coherence A moral belief that contradicts other well-justified commitments may require revision. Ethical reasoning therefore involves examining whether one's judgments can form a coherent set rather than treating each judgment in isolation.

Fifth, the judgment should be open to critical challenge. A belief that cannot survive examination, counterargument or relevant evidence is a weak candidate for knowledge. Openness to revision is not a weakness of ethical knowledge; it is part of responsible epistemic practice. These conditions do not provide an algorithm for producing morally correct answers. Rather, they identify standards by which claims to ethical knowledge can be evaluated.

8. Ethical Knowledge and Professional Judgment

The philosophical argument has implications beyond academic ethics because professional decisions frequently contain normative assumptions.

The relevance, however, is not that each discipline possesses an entirely separate form of ethical knowledge. The deeper point is that professionals in different fields routinely make claims about what ought to be done and therefore face the same epistemological question: what justifies the ethical judgment?

In economics, for example, evidence about efficiency or growth may inform policy decisions, but efficiency alone does not settle questions of distributive justice. In accounting, compliance with formal requirements may be necessary, but compliance alone does not exhaust the question of professional integrity.

In education, treating learners identically may appear equal while producing inequitable outcomes; determining what is fair requires more than applying a numerical rule. In management, organisational interests may provide legitimate reasons for action, but those interests do not automatically determine what is morally justified toward employees, clients, communities or other stakeholders. These examples are not intended to develop four separate professional ethics frameworks. Their purpose is narrower: they demonstrate that the epistemological problem travels across disciplinary boundaries. In each case, a professional may possess substantial factual knowledge while still needing to justify the normative conclusion drawn from that knowledge.

Thus, professional competence requires more than knowing what is. It also requires the capacity to reason responsibly about what ought to be done and why.

9. Critical Discussion

The analysis developed in this paper supports neither the claim that ethical knowledge is straightforward nor the stronger claim that it is impossible.

First, the distinction between belief and knowledge is indispensable. Moral conviction, even when sincerely and strongly held, does not constitute knowledge merely by virtue of its intensity. Ethical knowledge requires justification. Second, justification itself is contested. Kant's rationalism demonstrates how universal principles may provide grounds for moral judgment; consequentialism demonstrates the importance of evidence about outcomes; Aristotle demonstrates that ethical judgment involves sensitivity to particular circumstances and practical wisdom. None of these approaches is free from difficulty. Their differences reveal that ethical justification is multidimensional. Third, the existence of moral disagreement should generate epistemic humility rather than immediate scepticism. Disagreement can reveal bias, conflicting principles, incomplete evidence or genuine uncertainty. It may also expose weaknesses in a moral theory. Nevertheless, disagreement does not logically establish that moral truth does not exist. Contemporary moral epistemology continues to treat this as an unresolved and substantive issue.

Fourth, empirical knowledge and ethical knowledge should not be conflated. Facts matter to moral judgment, but factual premises alone do not generate normative conclusions. The transition from is to ought requires explicit normative reasoning.

Finally, the paper's argument should not be interpreted as defending a particular substantive moral theory. Its concern is epistemological. The question is not whether Kantianism, consequentialism or virtue ethics provides the final answer to morality. Rather, the question is what would make a moral judgment epistemically defensible in the first place. This leads to a qualified conclusion: ethical knowledge is possible, but it is neither automatic nor infallible. A claim to know what is right is strongest when it is supported by relevant evidence, defensible moral reasons, coherent reasoning and critical reflection, while remaining open to correction. This position avoids both extremes: it rejects moral dogmatism without collapsing into moral scepticism.

10. Conclusion

Can we know what is right?

The analysis suggests that the answer is yes, but only in a qualified and fallibilist sense.

Ethical judgments can reasonably constitute knowledge when they are grounded in defensible reasons, informed by relevant facts, coherent with other justified commitments, and capable of surviving serious critical examination. Ethical knowledge therefore cannot be reduced to personal preference, social convention, emotional conviction or mere compliance with authority.

At the same time, moral knowledge is subject to important limitations. Human beings possess incomplete information, are vulnerable to bias, disagree about moral principles, interpret circumstances differently, and may reason from premises that later prove inadequate. Moral disagreement consequently provides an important reason for epistemic humility, but it does not establish that ethical knowledge is impossible.

The philosophical significance of the question therefore lies not in discovering a simple universal procedure for determining what is right. Rather, it lies in recognising that a moral claim requires epistemic justification if it is to be presented as knowledge.

The most defensible position emerging from this inquiry is consequently that ethical knowledge is possible as fallible, reasoned and critically revisable knowledge. We can have good reasons for believing that some actions are right or wrong without possessing infallible certainty about every moral question.

The central challenge, therefore, is not merely to make ethical judgments, but to be able to answer the deeper epistemological question:

What Justifies Us in Claiming That Our Judgment About What Is Right Is Knowledge Rather than Merely Belief?

That question remains open to philosophical examination, and precisely for that reason it continues to matter across disciplines and forms of professional decision-making.

11. The Philosophical Analysis Generates the Following

Implications for Ethical Reasoning and Professional Decision-Making a. Strengthen reasoned ethical deliberation Ethical decisions should not rest solely on personal conviction, authority, convention or intuition. Decision-makers should articulate the reasons supporting their judgments. b. Separate empirical evidence from normative judgment Professionals should distinguish between what the evidence shows and the moral principle used to determine what ought to be done. This directly reflects the article's discussion of Hume's is-ought problem. c. Make normative assumptions explicit Where ethical decisions depend on principles such as fairness, welfare, equality, rights or autonomy, those principles should be identified and critically examined rather than left implicit. d. Cultivate epistemic humility Because ethical knowledge is fallible, individuals should remain open to disagreement, new evidence, alternative interpretations and correction. e. Encourage structured ethical deliberation in professional practice Organisations and professional institutions can incorporate ethical reasoning into decision-making processes rather than treating ethics as merely compliance with rules. f. Promote interdisciplinary ethical reasoning Since the same epistemological problem arises across Economics, Accounting, Education and Management, ethical reasoning should be integrated into professional education and continuing professional development.