Free Will and Determinism (SACE Stage 2 Philosophy)
“Evaluate the debate between determinism, libertarianism and compatibilism about free will”
Determinism is the thesis that every event, including human choices, is fully fixed by prior causes and the laws of nature. If true, it seems to leave no room for free will, which matters because moral responsibility appears to require freedom. Hard determinists accept determinism and deny free will. Libertarians affirm free will and deny determinism. Compatibilists, such as Hume and Frankfurt, argue freedom and determinism are compatible. You should evaluate these positions.
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What this dot point is asking
You need to define determinism, explain the three main positions on free will, and assess which best preserves both science and responsibility.
The problem
Determinism is the view that the state of the world at any moment, together with the laws of nature, fixes every later state. Applied to human action, it implies that each choice is the inevitable product of prior causes reaching back before our birth. This seems to threaten free will, the capacity to have done otherwise, and with it moral responsibility, since we do not normally blame people for what they could not help.
Hard determinism
Hard determinism accepts determinism and concludes that free will is an illusion. Baron d'Holbach argued that humans are wholly part of nature and no more exempt from causal law than a falling stone. Modern hard determinists point to the way genes, upbringing and brain states shape decisions. The view is admirably consistent with a scientific picture of the world. Its cost is steep: it appears to abolish desert, praise and blame, and it clashes with the deep conviction that we sometimes genuinely choose.
Libertarianism
Metaphysical libertarianism, not to be confused with the political term, holds that we have genuine free will and that determinism is therefore false for human action. Some libertarians appeal to agent causation, the idea that a person, as a self, can originate a choice not fully fixed by prior events. Others point to indeterminacy in nature. The attraction is that it honours our experience of open deliberation and secures responsibility. The objection is that undetermined events look like random ones, and randomness seems no better than determinism for grounding genuine control, a worry sometimes called the luck objection.
Compatibilism
Compatibilism denies that freedom requires the absence of causal determination. David Hume defined freedom as the ability to act according to one's own desires without external constraint, which is fully consistent with those desires being caused. A prisoner is unfree; a person choosing dinner is free, even though both choices have causes. Harry Frankfurt deepened this by distinguishing first-order desires from second-order desires, desires about which desires to have. A person acts freely when they act on a desire they endorse at the higher level, which is why an addict who wishes not to want the drug is unfree in the relevant sense.
Compatibilism's strength is that it reconciles a scientific, causal worldview with everyday talk of responsibility. The standard objection is that it changes the subject: critics say it secures only freedom of action, not the deeper freedom to have ultimately willed otherwise, which is what genuine responsibility seems to require.
Evaluating
A strong answer notes that each position pays a price. Hard determinism keeps science but sacrifices responsibility. Libertarianism keeps responsibility but owes an account of how undetermined choices avoid being mere chance. Compatibilism keeps both but risks redefining freedom too thinly. Much depends on what concept of freedom genuine responsibility actually demands. The most defensible view is arguably a compatibilism enriched by Frankfurt's hierarchy, since it explains the difference between a free agent and a compelled one without denying that choices have causes.
The key move of compatibilism is to define freedom as acting on your own uncoerced desires rather than as being uncaused. This lets free will and determinism both be true at once, which is why the position is not simply a denial of determinism.
Each position pays a price; the marks come from weighing them. Work it in steps.
Step 1: state what responsibility seems to require
Identify the freedom at stake, the ability to have done otherwise, and why it matters for praise and blame.
Step 2: cost each position
Hard determinism keeps science but loses responsibility; libertarianism keeps responsibility but faces the luck objection; compatibilism keeps both but may redefine freedom thinly.
Step 3: test compatibilism with Frankfurt
Use second-order desires to distinguish a free agent from a compelled one, then press whether this is deep enough.
Step 4: defend a position
Conclude which best fits the concept of freedom responsibility demands. Positions costed against a clear notion of freedom and a defended verdict is what the top band rewards.
- Confusing metaphysical libertarianism with political libertarianism
- Here libertarianism is the claim that we have free will and determinism is false, nothing to do with politics.
- Assuming indeterminism guarantees freedom
- If a choice is merely random, it is not under the agent's control, so undetermined does not automatically mean free.
- Thinking compatibilism denies causes
- Compatibilists fully accept that choices are caused; they deny only that causation rules out freedom.
Assessment-style questions
Questions on this dot point, each with a worked answer, written by ExamExplained. Philosophy has no written exam, so use them to check your understanding before your assessment tasks.
Practice15 marks"If determinism is true, no one is morally responsible." Critically discuss the debate between determinism, libertarianism and compatibilism.Show worked answer →
A 15 mark essay needs a thesis, the three positions, their objections and a defended conclusion.
Define determinism. State that prior causes and laws fix every event, threatening the freedom responsibility seems to require.
Set out the three positions. Hard determinism (free will is illusory), libertarianism (free will real, determinism false) and compatibilism (both true).
Apply objections. Press hard determinism on responsibility, libertarianism on the luck objection, and compatibilism on whether it secures deep freedom.
Conclude. Defend a position, perhaps a Frankfurt-style compatibilism. Markers reward each position weighed and a defended thesis.
Practice12 marksEvaluate compatibilism as a solution to the free will problem.Show worked answer →
A 12 mark essay needs compatibilism explained, applied and judged.
Explain it. Hume defines freedom as acting on uncoerced desires; Frankfurt adds second-order desires, so an agent is free when acting on an endorsed desire.
Apply it. Show how it distinguishes a free chooser from a coerced agent or an unwilling addict.
Object. Press the changing-the-subject objection: it secures freedom of action, not the deeper freedom to have willed otherwise.
Judge. Conclude whether compatibilist freedom suffices for responsibility. Markers reward the deep-freedom objection engaged and a defended verdict.
Practise this
Sources & how we know this
- Stage 2 Philosophy subject outline (2025 onwards) — SACE Board
- Stage 2 Philosophy: external assessment — SACE Board