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Intro to Philosophy Unit 5: Free Will and Determinism

If every event is caused by earlier events and the laws of nature, can anyone act freely or deserve praise and blame? This unit maps the main answers: hard determinism, libertarianism and compatibilism.

Covers: Causal determinism, Hard determinism, Libertarianism and agent causation, Compatibilism, Frankfurt cases and alternative possibilities, Moral responsibility and reactive attitudes, Science and free will

Study guide

Causal determinism is the thesis that the state of the world at one time, together with the laws of nature, fixes everything that happens afterward. Laplace imagined an intellect that, knowing the position and force of every particle, could predict the entire future. Determinism is not fatalism, the idea that some outcome will happen no matter what we do; on determinism our choices still make a difference, but they are themselves caused. The free will debate starts from a question: is free will compatible with determinism? Incompatibilists answer no; compatibilists answer yes. Combining these with views about whether determinism is true gives the three main positions.

Hard determinists, such as Baron d'Holbach, accept incompatibilism and determinism, so they conclude no one is free in the sense needed for blame. Contemporary hard incompatibilists such as Derk Pereboom add that indeterminism would not help either. Libertarians, such as Thomas Reid, Roderick Chisholm and Robert Kane, accept incompatibilism but deny determinism, holding that some choices are undetermined. Chisholm appealed to agent causation, where the agent, not a prior event, causes the choice. Kane locates freedom in 'self-forming actions,' torn choices that shape character. The central objection is the luck problem: if nothing settles an undetermined choice, it seems random rather than controlled. Peter van Inwagen's consequence argument is the leading case for incompatibilism: we have no control over the past or the laws, so we have none over what follows from them.

Compatibilists, including Hobbes, Hume and many contemporary philosophers, argue that freedom means acting from your own desires and reasons, without coercion or compulsion. On this view the difference between a free and an unfree act is not whether it was caused but how: a choice caused by your own wants is free, while being pushed or threatened is not. Some compatibilists analyze 'could have done otherwise' as 'would have done otherwise if she had wanted to,' though critics point to agents who cannot want otherwise. Harry Frankfurt proposed a hierarchical view: you act freely when the desire that moves you is one you want to move you, as the addict who wants to quit does not.

Frankfurt also attacked the principle of alternative possibilities, which says you are responsible only if you could have done otherwise. In his cases, a hidden device would force a choice if the agent wavered, but he chooses on his own, so he seems responsible without alternatives. P. F. Strawson argued that responsibility rests on reactive attitudes such as resentment and gratitude, which a theory like determinism gives us no reason to abandon. Galen Strawson, by contrast, argued that ultimate responsibility would require creating yourself, which is impossible. Scientific findings such as Libet's readiness potential experiments have been read as threatening conscious will, though philosophers dispute what they show.

Key ideas

• Determinism says the past plus the laws of nature fix a unique future.
• Incompatibilists hold that free will and determinism cannot both be true; compatibilists hold they can.
• Hard determinists deny free will; libertarians deny determinism.
• The consequence argument and the luck objection are the central arguments on each side of libertarianism.
• Compatibilists define freedom as acting on one's own desires without coercion, and Frankfurt adds a hierarchy of desires.
• Frankfurt cases challenge the principle that responsibility requires the ability to do otherwise.
• Reactive attitudes and the basic argument offer contrasting accounts of moral responsibility.

Formulas and rules

Common mistakes

• Confusing determinism with fatalism, which says outcomes happen whatever we choose.
• Confusing metaphysical libertarianism with political libertarianism.
• Calling compatibilists determinists who deny free will; they affirm free will.
• Assuming quantum indeterminism automatically gives free will, ignoring the luck objection.
• Thinking Frankfurt cases show determinism is false; they target the link between responsibility and alternatives.

Before the test, make sure you can

• Define determinism and distinguish it from fatalism.
• Classify hard determinism, libertarianism and compatibilism by their stance on incompatibilism and determinism.
• Explain the consequence argument and the luck objection.
• Explain classical compatibilism and Frankfurt's hierarchical view.
• Analyze a Frankfurt-style case and what it shows about alternative possibilities.
• Compare P. F. Strawson's and Galen Strawson's views on moral responsibility.
• Evaluate what experiments like Libet's can and cannot show about free will.

Words to know

Causal determinism

The view that every event is fixed by prior events together with the laws of nature.

Fatalism

The view that certain outcomes will happen no matter what anyone chooses.

Incompatibilism

The view that free will and determinism cannot both be true.

Compatibilism

The view that free will is compatible with determinism; also called soft determinism.

Hard determinism

The view that determinism is true and so free will does not exist.

Libertarianism (free will)

The view that free will exists and is incompatible with determinism, so determinism is false.

Agent causation

The libertarian idea that an agent, not a prior event, directly causes a free choice.

Self-forming action

Kane's term for an undetermined, torn choice that shapes an agent's character.

Luck objection

The objection that undetermined choices would be random rather than controlled.

Consequence argument

Van Inwagen's argument that if our acts follow from the past and laws, which we do not control, we do not control our acts.

Principle of alternative possibilities

The principle that a person is responsible only if they could have done otherwise.

Frankfurt case

A scenario where an agent could not have done otherwise but still seems responsible.

Second-order volition

Frankfurt's term for wanting a certain desire to be the one that moves you to act.

Reactive attitudes

P. F. Strawson's term for responses like resentment, gratitude and indignation that ground responsibility practices.

Basic argument

Galen Strawson's argument that ultimate responsibility requires impossible self-creation.

Laplace's demon

An imagined intellect that could predict the whole future from complete knowledge of the present.

Readiness potential

Brain activity that Libet found began before subjects reported deciding to move.

Sample practice questions

30 more questions like these, from level 1 to 5, are in the practice set.