Who Decides What’s Right? The Philosophers Who Built Morality
The Schoolyard Standoff
Imagine four friends arguing on the playground. One says the rules of tag are unfair and wants to change them. Another insists the rules are just how it works and can’t be changed. A third thinks everyone should just feel what’s right, while the fourth wonders if you can even argue about made-up rules.
This is a small version of a huge problem. People disagree deeply about right and wrong, about justice and fairness. Some think lying is always wrong. Others think it depends on who you’re protecting. Some believe property should be shared. Others think ownership is sacred. If everyone just claims that their view is the single real truth, the argument never ends. Each side just says the other is blind.
The 20th-century philosopher John Rawls (1921–2002) thought this stalemate was the most important problem in moral thinking. He looked back to the 18th-century thinker Immanuel Kant (1724–1804) and found a radical new idea: maybe moral truth isn’t something we discover, like a far-off mountain. Maybe we build it.
Immanuel Kant’s Radical Idea: Reason Builds the Law
Before Kant, many philosophers thought morality came from one of two places. First, some said we just feel it. Thinkers like David Hume (1711–1776) argued that moral judgments come from our sentiments, like a gut feeling of approval or disgust. In this view, your reason just helps you figure out how to reach a goal you already desire. It’s like a GPS: it can find the fastest route to the ice cream shop, but it can’t tell you if you should want ice cream at all.
Kant saw a problem here. If morality is just about our feelings and interests, then moral rules only bind us when we happen to care. Their authority is conditional — they are not truly required in a deep way.
Second, others said we discover moral truths with our minds, like spotting a math fact. This was called dogmatic rationalism, championed by thinkers like Christian Wolff (1679–1754). In this view, reason just sees objective moral values that exist out there, independently of us. But for Kant, this made humans too passive. We would just be receiving signals from outside, not actively deciding. And again, those truths would only guide us if we already desired to follow what is rational.
Kant diagnosed a shared failure. Both sides doubted the power of pure reason to actually command us. They made morality dependent on something outside reason itself — our feelings, or some external moral reality. Kant called this heteronomy. He thought it was a form of moral skepticism, the idea that reason alone can’t really tell us what we must do.
The Categorical Imperative: A Principle You Give Yourself
Kant’s solution was to say that reason can be autonomous. The word means self-legislating. Reason does not get its authority from anything outside it. Instead, reason is a self-governing activity with an internal rule. Kant called this internal rule the Categorical Imperative.
What is this rule? At its simplest, it requires that when you deliberate about what to do, you test your motive by a standard. Can the principle behind your action be endorsed as a universal law, one that applies to everyone with reason? If your plan only works because you make a special exception for yourself — like lying to get what you want — it fails the test.
The philosopher Christine Korsgaard (born 1952) developed this into what she called procedural realism. There are right answers to moral questions, not because they refer to a pre-existing moral reality out there, but because there are correct procedures of practical reasoning for arriving at them. This is the difference between discovering a rule and constructing it through a process you can justify. The procedure is what matters, and it involves reflecting on whether your reasons could make sense to anyone.
But this creates a deep question. If we make the law ourselves, doesn’t that mean a bully can just make up a law that bullying is fine? Korsgaard argues no, because this isn’t about arbitrary personal choice. A rational agent must act on universal principles to maintain their own integrity as an agent. A person who just acts on mindless urges isn’t really governing themselves at all. To act at all is to commit yourself, at least a little, to making sense.
Why Not Just Make a Deal With Each Other?
Another branch of constructivism takes a less demanding path. The philosopher Thomas Scanlon (born 1940) focused specifically on the morality of right and wrong, rather than all of normativity. He proposed a powerful formula: an act is wrong if it would be prohibited by any set of principles that no one could reasonably reject as a basis for informed, unforced, general agreement.
Think of it as the ultimate group project rule. You aren’t trying to prove a metaphysical law of the universe. You are looking for a principle everyone in the group would have to accept, assuming they were reasonable and not just selfish. This is a contractualist method — a hypothetical agreement among equals. The property of being “wrong” is constituted by what reasonable people, under these conditions, would find non-rejectable.
This approach doesn’t claim to answer every single question about reasons. Scanlon acknowledges that we often just make substantive judgments about what reasons we have. But for the central territory of right and wrong, the test of what others cannot reasonably reject does the crucial work. It builds morality from the structure of justifying ourselves to one another.
The Aristotelian Alternative: Growing a Good Character
Not everyone thinks good reasoning is about law-like universal rules. Aristotelian constructivists argue that practical reason is grounded in a substantive picture of a good life. For them, the standard for right action isn’t a formal procedure but the judgment of a wise and virtuous person.
Think of learning to play the piano. You don’t just learn a set of abstract rules that never change. You train your hands, your ear, and your sense of rhythm. Your emotions and bodily instincts are reshaped by practice until you develop a “second nature.” For Aristotle, this is how moral character works too. Through habituation and education, reason transforms our animal sensibility. The norms of good conduct are the work of practical wisdom, or phronesis.
This view starts with a critique of Kant. Some say his universal principles are too rigid and can’t adapt to the rich complexity of real situations. An Aristotelian builder works the other way around: they look at what a fully flourishing human life actually requires, and from that substance, the principles emerge. The standard is not a law written in the sky, but the life of a specific, mature human being who has learned to feel and act well.
The Euthyphro Problem: A Question That Loops Back
There is one classic challenge all constructivists must face, and it comes from the ancient Greek philosopher Plato. In the dialogue Euthyphro, Socrates asks a devastating question: is something good because the gods love it, or do the gods love it because it is good?
The metaethical version of this dilemma is as follows. Either the process of rational construction is subject to independent moral constraints, or it is not. If it is not, then the procedure seems arbitrary — why should we trust its results? It might spit out principles that feel completely wrong to us. If the procedure is constrained by correct moral intuitions we already have, then it seems those intuitions are the real foundation of morality, and the constructivism is just a fancy show hiding a form of realism. We wouldn’t be building morality; we would just be rediscovering it with extra steps.
Constructivists reply that this is a false choice. Onora O’Neill (born 1941), a leading Kantian, argues the vindication of practical reason is avowedly circular. Reason critiques its own claims. We find out what the principles are by submitting them to public, critical debate. The authority of reason isn’t handed down from a set of silent, unconstructed facts; it is conferred by a continuous, open conversation among finite, interdependent beings who must coordinate their lives. The process isn’t arbitrary because it is constrained by the very purpose of reasoning: to offer standards that are followable by others.
So, Do You Find Rules or Make Them?
Why does this abstract architecture matter to you? Because every time you face a conflict between what you feel is right and what a rule says, you are standing in this debate. When you tell a friend, “That’s not fair,” are you pointing to a fact about the universe, or are you making a claim that you think would survive a conversation between equals?
The disagreement between Hume’s feelings, Kant’s self-given law, Aristotle’s wise character, and the strict realist’s discovered fact is not a dusty museum piece. It’s a live map of your own head. The question of whether you are a discoverer or a builder of moral truth is one of the few questions that matters every single day you spend with other people.
Think about it
- If a new student joins your school and deeply believes a rule your group made is unfair, do you change the rule to make life better for them, or keep it because you all agreed on it before? What decides?
- Can you imagine a brilliant, perfectly logical villain who understands all the facts but simply doesn’t care about being cruel? If so, what is the argument that they are making a mistake?
- Think of a time you stopped yourself from doing something because it “wouldn’t be fair to everyone.” Where do you think that stopping power came from — a feeling, a thought, or something else?
