Free will and determinism: hard determinism, libertarianism and compatibilism

What this dot point is asking

This dot point addresses the free will strand of the TASC Philosophy course, which examines hard determinism, soft determinism and libertarianism. You are asked to define each position, present the central arguments, and evaluate what is at stake for moral responsibility.

Determinism and the threat to freedom

Determinism is the thesis that, given the past and the laws of nature, only one future is possible. If your choices are just later links in a causal chain stretching back before your birth, it can seem you could never have done otherwise. The clearest statement is Peter van Inwagen's consequence argument: if determinism is true, our acts are consequences of the laws of nature and events in the remote past; but we have no control over those, so we have no control over their consequences, including our acts.

Hard determinism

Hard determinists accept determinism and conclude that free will and moral responsibility are illusions. If no one could have acted otherwise, no one truly deserves blame or praise. Baron d'Holbach defended this in the eighteenth century, and modern hard incompatibilists like Derk Pereboom argue we should give up the notion of basic desert while keeping forward-looking practices like rehabilitation. The strength of the view is its honesty about causation; its cost is that it overturns deeply held practices of holding people accountable.

Libertarianism

Libertarians, not to be confused with the political view of the same name, hold that we have genuine free will and that determinism is therefore false for human action. Some appeal to agent causation, defended by Roderick Chisholm, on which a person, as a substance, originates actions without being determined to do so. Others point to indeterminism in physics. The view preserves robust responsibility but faces the luck objection: if a choice is not determined by anything about the agent, including their reasons, it looks random rather than free, which is no better for responsibility than determinism.

Compatibilism

Compatibilists, also called soft determinists, argue that freedom and determinism are compatible because freedom is not the absence of causation but the absence of constraint. David Hume held that a free action is one that flows from your own will rather than external compulsion or coercion. A prisoner in chains is unfree; a person choosing what to eat is free, even if that choice has causes. Harry Frankfurt deepened this by locating freedom in acting on desires you reflectively endorse: an addict who wants to be rid of the craving but cannot is unfree, while one who endorses their desire acts freely.

Evaluating the debate

A strong answer weighs the trade-offs. Hard determinism is consistent but revisionary about responsibility. Libertarianism protects responsibility but must explain how undetermined choices are not merely lucky. Compatibilism saves both determinism and everyday responsibility but is accused of changing the subject, offering a freedom too thin to ground the deep desert we care about. Frankfurt-style cases, in which a person acts on their own reasons but could not have done otherwise because a neuroscientist stood ready to intervene, are widely used to argue that responsibility does not actually require alternative possibilities. For the exam, take a position and defend it against the strongest rival.