A common objection to determinism is the claim that if human beings lack free will, punishment becomes impossible or unjustified. This worry rests on a misunderstanding of what punishment is for. Punishment need not be grounded in the idea that a person is the ultimate, self-created author of their actions. Instead, punishment can be understood as a social response to harmful behaviour that aims to protect others, discourage future harm, and signal moral boundaries. Under this view, punishment is not about “paying someone back” but about refusing to cooperate with wrongdoing, and it must always be humane.
Reward and Punishment Are Not Symmetrical
Rewarding and punishing are often treated as mirror images, but they are morally asymmetric. Rewards are generally forward-looking and beneficial; they encourage desirable behaviour. Punishment, by contrast, inflicts harm in response to past actions that cannot be undone. This difference matters.
Even if rewards are imperfectly justified—because luck, upbringing, and natural ability play a major role in success—the harm involved is minimal. Punishment, however, deliberately causes suffering for an act that is already fixed in the past. Causing suffering for what cannot be changed requires stronger justification than providing a benefit, and retribution alone cannot supply that justification.
If punishment is defended solely as deserved suffering for past wrongdoing, it becomes morally suspect. The present and future matter more than the unalterable past. Inflicting suffering simply because someone “deserves it” serves no corrective or protective purpose.
Free Will Does Not Necessarily Ground Punishment
If wrongdoing is understood as the product of distorted judgment, compulsion, or psychological disorder, then punishment justified as retribution becomes indistinguishable from punishing illness. That is not justice but cruelty. Nobody agrees on what exactly to do with somebody who has committed a very specific crime. Nobody can prove their punishment really was objectively just.
Appeals to free will do not solve this problem. No human institution can know with certainty a person’s precise desert, intentions, degree of responsibility, or the internal pressures influencing their behaviour at the moment of action. Memory is unreliable, emotions distort self-assessment, and external observers have even less access to a person’s inner state. For that reason, punishment based on claims about ultimate moral responsibility is inevitably speculative.
Only an omniscient being could, in theory, assign perfectly proportionate blame. But even then, if all actions are shaped by factors beyond the agent’s control, universal forgiveness would follow rather than punishment. This exposes the incoherence of doctrines that combine determinism, inherited guilt, and eternal punishment.
I would suggest here that if we think a determinist believing world would be harmfully unjust, we do not know if the free will believing world was any better. There is no proof that "deserving" matters much.
Determinism and Moral Response
Determinism does not deny that people do harmful things. It denies that people are evil in themselves. Under determinism, moral responses focus on harm prevention, rehabilitation, and social protection rather than condemnation.
Forgiveness, properly understood, does not require judging someone as metaphysically guilty in the strongest sense. It requires recognising harm while rejecting hatred and revenge. Determinism allows for this more consistently than free-will doctrines that insist on desert as the basis of moral judgment.
Free Will and Social Policy
Belief in free will is often used to justify punitive social policies. For example, people who develop illnesses through addiction or risky behaviour are sometimes said to “deserve” lower priority in healthcare. This follows naturally from the idea that individuals freely choose their suffering.
Determinism rejects this conclusion. People are shaped by prior causes, many of which they did not choose. Compassion does not require approval of harmful behaviour; it requires recognition that suffering is not a moral achievement. Medical care should respond to need, not moral judgment.
Free Will and Moral Fashion
Moral beliefs vary dramatically across cultures and historical periods. Practices once considered virtuous—such as religious persecution or criminalisation of homosexuality—are now widely condemned. This variability undermines the idea that individuals can always be blamed for knowingly choosing evil. People often sincerely believe their actions are right according to the standards they have inherited.
Punishing someone for acting on deeply held but mistaken beliefs risks collapsing into punishment for ignorance or limited understanding—conditions that are themselves largely unchosen.
Law Without Retribution
The purpose of law is public safety and social order, not moral revenge. Legal consequences can be justified without invoking free will by focusing on deterrence, incapacitation, and rehabilitation. A person may be confined even if they believed they were acting rightly, just as someone with a dangerous illness may be quarantined without being blamed.
This is not “punishment” in the retributive sense but harm prevention.
Why Free Will Persists
The strongest motivation for belief in free will is the desire to justify rewards and, especially, punishment. Yet in practice, even those who profess belief in free will do not reward or punish inner motives; they respond to outward behaviour and its consequences. Determinists can do exactly the same without pretending that suffering is deserved in some ultimate sense.
Rewards function by encouraging behaviour and satisfying social desires, not by recognising metaphysical merit. Punishment, when justified at all, should aim at protection and reform, not retaliation.
Conclusion
We can deny free will without losing moral structure, social order, or accountability. What we must abandon is the idea that suffering is justified simply because someone “deserves” it. Once that idea is rejected, punishment is transformed from an act of revenge into a practical, limited, and humane response to harm.
Nothing essential is lost—and much cruelty is avoided—by letting go of the dogma of free will.