The lecture opens by inviting students into a Justice course through a simple but unsettling claim: we all make moral judgments every day, yet we rarely stop to ask why we judge the way we do. To surface those hidden assumptions, the professor begins with the most famous thought experiment in modern ethics—the trolley problem—because it forces fast, instinctive answers and then makes those answers feel difficult to justify.
First comes the driver version of the trolley case: a trolley is about to kill five workers, but the driver can turn the wheel and divert it onto another track where it will kill one. In the room, most people say they would turn the trolley. The professor uses that near-consensus to introduce the basic logic of consequentialist thinking: if moral reasoning is about results, then saving five lives at the cost of one seems not only acceptable, but required. The point isn’t that this is the correct answer—it’s that the answer comes easily to many people, which suggests we have a strong intuitive attraction to weighing outcomes.
But the lecture immediately complicates that comfort with the bridge version: this time, you are not the driver; you are a bystander standing above the track next to a very large man. The trolley is again headed toward five. The only way to stop it is to push the man off the bridge so his body blocks the trolley, killing him but saving the five. Suddenly, even students who were confident in the driver case hesitate or refuse. The professor presses on the tension: the numbers are the same—five versus one—so why does our judgment shift? This is the first major lesson of the lecture: moral intuitions are not purely mathematical. The way harm is caused—directly vs. indirectly, personally vs. impersonally—changes how people feel about an action, even when the outcome is identical.
To broaden the point beyond trains, the professor moves to medical analogies. An ER doctor faces five moderately injured patients and one severely injured patient: most people prioritize saving the five. Again, that seems outcome-driven. But the final medical case hits like the bridge scenario: a transplant surgeon could kill one healthy person and use the organs to save five dying patients. Almost everyone rejects this as morally grotesque. The lecture highlights the pattern: people often accept sacrificing one to save five in situations that feel like redirecting harm or choosing between unavoidable deaths, yet they strongly reject actions that require using a person as a tool—especially an innocent person who is not already at risk.
From these reactions, the professor introduces the core philosophical tension that will organize the course. On one side is consequentialism, the family of views that judges actions by their outcomes and treats “maximize good consequences” as the guiding moral rule. On the other side is what the lecture calls categorical moral reasoning: the idea that some actions are wrong in themselves, regardless of how beneficial the results might be. This is where the class begins to feel the pull of rights, duties, and constraints—the sense that there are lines we shouldn’t cross, even for a better total outcome.
To show that these puzzles aren’t only classroom games, the lecture pivots to a real case: Queen v. Dudley and Stephens. After a shipwreck, four sailors are stranded without food or water. In desperation, the captain and first mate kill the cabin boy, Richard Parker, and cannibalize him so they can survive. When they are rescued, they are charged with murder. Here the moral pressure returns in a real-world form: the defendants claim necessity—that they did what had to be done to save lives. The professor uses the case to force the same question the trolley problem raised: can killing be justified by outcomes when the alternative is multiple deaths?
Class discussion reveals multiple moral fault lines. Some students sympathize with the survival argument: if death is imminent, isn’t it rational to choose the option that saves more people? Others insist that murder remains wrong even in desperation, and that allowing necessity as a defense risks turning basic rights into optional rules whenever circumstances become extreme. The lecture then introduces two “complications” that many people instinctively reach for: fair procedure (what if they had held a lottery?) and consent (what if the cabin boy had agreed?). But even these don’t fully resolve the discomfort. A lottery can feel fairer, yet some argue it cannot make killing permissible. Consent seems important, yet others question whether consent under starvation and terror is truly free—or whether it can ever legitimize being killed.
By the end of Part 1, the lecture has done something very specific: it has taken moral confidence and replaced it with moral inquiry. The professor doesn’t claim that one side has already won. Instead, the goal is to reveal that we carry competing principles at once—concern for overall welfare, respect for individual rights, discomfort with direct violence, and intuitions about fairness and consent—and those principles collide under pressure. That collision is not a failure of thinking; it’s the starting point of philosophy.
Finally, the lecture frames what the course will do next. It will use these dilemmas as a doorway into major traditions in moral and political philosophy—especially utilitarianism (associated with thinkers like Jeremy Bentham and later John Stuart Mill) and Kantian ethics (grounded in categorical duties and the categorical imperative). And it warns students: philosophy is not only abstract. It can be personally and politically disruptive because it forces you to reconsider beliefs you may have treated as obvious. Skepticism—the temptation to say “there’s no real answer”—is acknowledged, but the professor argues we can’t escape moral reasoning anyway. We still vote, judge, punish, forgive, and justify. Even refusing to decide becomes a decision with consequences.
So Part 1 ends with the course’s central promise: not to hand out easy answers, but to teach students how to examine the reasons behind their moral instincts—especially when those instincts conflict—because questions of justice are unavoidable, in law, in politics, and in ordinary life.
Part 2
After establishing the clash between “maximize outcomes” and “some acts are off-limits,” the lecture shifts into why this clash matters for justice, not just for hypothetical puzzles. The professor’s move is strategic: he treats the trolley cases as a diagnostic tool—something that exposes the structure of our moral intuitions—then asks what a society should do when citizens disagree about the right structure.
He starts by naming what many students were already doing without realizing it: counting lives and weighing costs is not random—it resembles a moral theory. This is where the course begins to introduce utilitarianism as a disciplined version of consequentialism. If the driver case feels correct to many people, that is partly because it fits a very powerful idea: morality should reduce suffering and increase well-being, and justice should be designed to do the same. The professor emphasizes that utilitarianism is attractive because it seems impartial: it doesn’t care who the five are or who the one is; it treats each life as equally valuable. That impartiality feels like fairness.
But the lecture doesn’t let utilitarianism “win” by default. It highlights the reason people recoil in the bridge and transplant cases: even if the math works, many of us feel there’s something wrong with treating a person as a tool. That moral resistance is not a vague emotion; it points toward another tradition where justice is about rights, respect, and limits. The professor sets up the next big question: if a society tries to maximize welfare, can it accidentally justify cruelty so long as it benefits the majority? And if a society builds strict rights into its laws, can it block actions that would prevent large-scale harm?
To make this practical, the lecture reframes the dilemmas as conflicts between two kinds of moral reasoning:
- A results-first approach: “What outcome produces the most good (or least harm) overall?”
- A principle-first approach: “What actions are forbidden or required no matter what outcomes they produce?”
The professor stresses that the hardest part is not choosing one label or the other—it’s explaining why certain acts feel forbidden. Students often say, “Because it’s murder,” but the lecture pushes further: why should murder be categorically wrong if the alternative is more deaths? When students answer “because of rights,” the professor presses again: where do rights come from, and how do we justify them?
This is where the case of Dudley and Stephens becomes a bridge to political philosophy. In court, “necessity” sounds like an outcome-based defense: killing one prevented the death of all. But the legal system rejected that logic, effectively saying: even extreme circumstances do not erase the rule against intentional killing. The professor uses this to show a major theme in justice: law often represents society’s decision to draw a line—sometimes a hard line—because allowing exceptions can create a dangerous precedent.
Then the lecture introduces two powerful “fixes” people try to apply when they feel torn:
- Fair procedure: If a lottery had been used, would the killing feel less like murder and more like a tragic but fair sacrifice?
- Consent: If the victim agreed, would it become morally permissible?
The professor treats these not as solutions but as lenses. The appeal of a lottery suggests that process matters in justice, not just outcomes. People care about whether a decision was made fairly, not only whether it produced a good result. Meanwhile, consent reveals another deep intuition: it matters whether someone’s rights were violated against their will. But the lecture also points out why these fixes are unstable. Consent can be coerced by circumstances. A lottery can be “fair” yet still violate the idea that you do not intentionally kill an innocent person. The lecture’s point is that justice is not a single value; it is a collision of values—welfare, rights, fairness, dignity, and responsibility.
By the end of Part 2, the lecture has raised the stakes: the course is not about trains, bridges, or lifeboats. Those are only training grounds. The real subject is how we design laws and institutions when moral reasoning pulls in opposite directions—when maximizing good conflicts with respecting individuals, and when procedure conflicts with outcomes. The course promises to examine these tensions through major philosophers, and to test them against real controversies where the “right answer” affects lives, liberty, and power.
Part 3
Part 3 functions like a launch ramp for the rest of the course. Having shown that our instincts diverge and that both outcome-based and principle-based reasoning have force, the professor turns to the course’s core mission: to study competing theories of justice and see what they imply for society.
He begins by previewing the thinkers as if they are rival architects designing different moral worlds.
Utilitarianism (Bentham, and later Mill) will argue, in its strongest form, that justice should aim at the greatest overall well-being. The professor explains why this view is not merely “cold math.” It is a moral demand for impartiality: each person’s happiness counts, and no one’s happiness counts more simply because of status or power. In a society with massive inequality, that can be revolutionary. Bentham’s approach also pushes toward measurable policy questions: what laws reduce suffering? what institutions create flourishing? This is the side of moral reasoning that naturally connects to reforms, cost-benefit analysis, and public welfare.
But the lecture is careful to show the haunting question utilitarianism must answer: what if maximizing welfare requires sacrificing an innocent person, humiliating a minority, or violating someone’s rights? The transplant case is not a childish trick; it’s a warning sign. If your theory can justify killing one healthy person to save five, then your theory must explain why that conclusion is not monstrous—or else modify itself to avoid it. This sets up why the course cannot stop at “maximize happiness” without examining deeper constraints.
Then comes the rival vision, associated with Kant and categorical moral reasoning. The professor sketches the idea that morality is not a tool for producing outcomes but a framework for respecting persons. People are not objects to be used; they have dignity and must be treated as ends in themselves. The lecture connects this directly to why students resist pushing the man off the bridge or harvesting organs: even when the outcome looks better, the means feel like a violation of what a person is. In this view, justice is not primarily about maximizing happiness; it is about honoring duties, rights, and the moral equality of persons in a way that cannot be traded away.
But Part 3 also underscores that categorical reasoning has its own burden. If you refuse to violate a rule even when catastrophe is looming, you must explain why adherence to duty matters more than preventing large-scale harm. Students often feel this tension when they imagine being the one who could divert the trolley but refuses: five people die because you would not actively cause one death. Is that moral integrity—or moral irresponsibility? The professor doesn’t settle it; he uses it to show that every theory of justice carries costs, and those costs must be faced honestly.
At this point, the lecture widens from ethics into political life. Justice is not only about individual choices; it’s about laws, rights, punishment, freedom, and equality. The professor signals that the course will connect moral theory to controversies such as:
- when (if ever) the state may coerce people (like conscription),
- what equality requires (formal equality vs. substantive fairness),
- how to think about liberty, property, and obligations to others,
- and how public policy should balance welfare against rights.
A key emphasis in Part 3 is that philosophy is dangerous in a particular way: it doesn’t let you hide behind tradition, slogans, or inherited opinions. Students are warned that they may discover arguments that challenge political identities, religious assumptions, or “common sense” beliefs. The lecture frames this as both a risk and a promise. The risk is discomfort: once you see the structure of an argument, you can’t unsee it. The promise is clarity: instead of reacting with instinct alone, you can understand what principle you are using and what that principle commits you to.
The professor also addresses a common escape route: skepticism, the belief that these moral questions can’t be answered objectively, so debate is pointless. The lecture concedes that certainty is hard, and disagreement is persistent. But it rejects the idea that disagreement makes reasoning useless. Even if we can’t prove a final answer the way we prove a math theorem, we still must choose laws, leaders, and policies—and those choices implicitly rely on moral judgments. The point of philosophy is not to end disagreement forever; it is to make disagreement more intelligent, more honest, and less driven by unexamined prejudice or reflex.
Part 3 ends by returning to the underlying motive of the whole course: justice is not just “what the law says,” and it’s not just “what feels right.” Justice is what we can defend with reasons—reasons that survive pressure, counterexamples, and real-world complexity. The trolley problem is the hook, but the real aim is bigger: to learn how to argue about the moral structure of a society, how to evaluate competing ideals of fairness and freedom, and how to recognize what we owe to each other as citizens and human beings.
