Libertarian Free Will

Compatibilists say:

freedom can exist inside causation.

Libertarians disagree.

They argue that at least some genuinely free choices must not be fully determined by the past.

This is libertarian free will.

Not Political Libertarianism

The term here concerns metaphysics.

It does not refer to:

• political ideology,
• economic policy.

Libertarian free will is a theory of agency.

Core Commitments

Libertarian theories usually accept:

1. free will exists,
2. free will is incompatible with determinism.

Therefore some human actions must be indeterministic in the relevant sense.

Why Incompatibilism?

If the exact same past plus laws guarantee one future, the libertarian asks:

In what sense could I really have chosen otherwise?

Freedom seems to require an open future.

Alternative Possibilities

Libertarianism often preserves a strong reading of:

I could have done otherwise.

Not merely:

If I had wanted differently…

but:

with the past fixed, more than one action remained possible.

Sourcehood

Some libertarians focus less on alternatives and more on sourcehood.

The agent must originate the action in a way not reducible to prior determining causes.

This makes the person a genuine source.

The Central Difficulty

Indeterminism creates openness.

But openness is not yet control.

If the choice is partly random, how is it more free?

This is the luck objection.

The Luck Objection

Suppose Alice is deciding whether to tell the truth.

Her reasons are evenly balanced.

An indeterministic event tips the decision toward truth.

Why is that outcome more attributable to Alice than a random coin flip?

Randomness vs Agency

Libertarians therefore need more than randomness.

They need indeterminism that is still:

• controlled,
• reason-sensitive,
• authored by the person.

This is the central engineering problem of the theory.

Three Broad Families

Libertarian accounts often fall into three families:

• event-causal,
• agent-causal,
• noncausal.

Each tries to combine openness with authorship differently.

Event-Causal Libertarianism

On an event-causal account, ordinary mental events cause action.

Examples:

• reasons,
• intentions,
• desires.

But the causal chain is not deterministic.

More than one outcome remains possible.

Robert Kane

Robert Kane is strongly associated with event-causal libertarianism.

He focuses on difficult moments of internal conflict.

These are called self-forming actions.

Self-Forming Actions

A self-forming action occurs when a person is torn between competing motivations.

Example:

• help someone,
• pursue personal ambition.

The decision is not predetermined.

Whichever choice occurs helps shape future character.

Why Self-Forming Actions Matter

Kane does not require every free action to be indeterministic.

Later actions may flow deterministically from a character partly formed through earlier undetermined choices.

This localizes indeterminism.

Effort of Will

In moments of conflict, Kane proposes competing neural processes may both receive effort.

Indeterminism in the struggle does not automatically make the result accidental because the agent actively endorses whichever reason succeeds.

Dual Effort

Imagine a businesswoman rushing to an important meeting.

She sees someone in distress.

Part of her wants to help.

Part wants to continue.

She struggles.

If she helps, that reflects one reason.

If she continues, that reflects another.

Both outcomes can be intelligible.

Luck Returns

Critics reply:

if exactly the same total state could lead to either outcome, what explains which one actually occurs?

If nothing further explains it, luck remains.

Kane’s Response

Kane argues the agent can be responsible for either outcome because:

• both motivations are hers,
• both efforts are intentional.

Indeterminism occurs inside agency, not outside it.

Whether this defeats luck is debated.

Agent Causation

Agent-causal theories take a different route.

The agent, not merely prior events, causes the action.

This is meant to create genuine sourcehood.

Substance Causation

On this view, persons are substances capable of initiating causal chains.

An agent causes:

decision D

without that causation being fully reducible to prior event causes.

Roderick Chisholm

Roderick Chisholm defended a form of agent causation.

He distinguished:

• event causation,
• immanent causation by an agent.

The agent becomes an originator.

Timothy O’Connor

Contemporary agent-causal theories have been developed by philosophers such as Timothy O’Connor.

They attempt to make agent causation metaphysically respectable.

Why Agent Causation Is Attractive

It directly addresses sourcehood.

The action happens because:

the person caused it.

Not because:

a random event selected one branch.

The Mystery Objection

Critics ask:

How does an agent cause an event without prior determining causes?

If the agent has reasons, why does one reason win?

If there is no sufficient explanation, arbitrariness returns.

Agent as Cause

The agent-causal reply is:

the explanation terminates in the agent.

Just as fundamental physical causation may not reduce further, agent causation may be basic.

This is a substantial metaphysical commitment.

Noncausal Libertarianism

Some theories deny that free action needs a standard causal chain at all.

Actions may be guided by reasons without being caused by them in the ordinary event-causal sense.

This view avoids some causal problems.

The Intelligibility Challenge

But if reasons do not cause the decision, how do they explain it?

A free action should not be disconnected from:

• evidence,
• values,
• goals.

Otherwise rational agency weakens.

Reasons Must Matter

A successful libertarian theory must preserve:

reason-responsiveness.

If reasons merely surround a random choice, freedom is not improved.

Deliberative Weight

Perhaps reasons influence probabilities without determining outcomes.

Then agency is probabilistic but structured.

The question remains whether probabilistic influence yields authorship.

Frankfurt Cases

Libertarians must also respond to Frankfurt-style cases.

If a person can be responsible without alternatives, perhaps openness is not necessary.

Libertarian Response

Some argue Frankfurt cases never truly remove all alternatives.

There may remain:

• flickers of freedom,
• alternative mental pathways.

Others shift toward sourcehood rather than alternatives.

Source Incompatibilism

A libertarian can say:

Even if alternatives are unnecessary, the action must not be fully determined by factors outside the agent.

What matters is ultimate sourcehood.

Manipulation

Manipulation cases support this intuition.

A person whose values are implanted may act reasons-responsively.

Yet we hesitate to call the action fully free.

Historical source matters.

Ultimate Responsibility

Libertarians often want a stronger form of responsibility than compatibilists.

The person is not merely a functioning decision system.

They are, in some sense, a true originator.

Self-Creation Problem

But no agent creates themselves entirely.

This is Galen Strawson’s challenge.

How can libertarian sourcehood avoid demanding impossible causa sui status?

Partial Self-Formation

One answer is:

ultimate responsibility does not require creating your initial self.

It requires participating indeterministically in later self-formation.

The person becomes partly author of who they become.

Recursive Character Formation

A few undetermined self-forming actions can shape:

• habits,
• priorities,
• identity.

Future choices then express that character.

This gives libertarian freedom temporal depth.

Development

Human agency matures gradually.

Children do not begin as fully autonomous choosers.

A libertarian theory therefore needs a developmental story.

Responsibility Comes in Degrees

Even if libertarian freedom exists, capacities vary.

Factors such as:

• coercion,
• addiction,
• cognitive impairment

can reduce responsibility.

Libertarianism need not imply all-or-nothing freedom.

Neuroscience

A libertarian does not need decisions to occur outside the brain.

Indeterministic agent control could, in principle, be realized neurally.

The theory is metaphysical, not necessarily dualist.

Dualist Libertarianism

Some libertarians do adopt soul-based views.

An immaterial self may initiate action.

This creates the familiar interaction problem.

Physicalist Libertarianism

Others attempt to place indeterministic agency fully inside physical nature.

This avoids substance dualism.

It requires physical processes compatible with non-determined control.

Quantum Temptation

Quantum mechanics appears to offer indeterminism.

This can seem like exactly the opening libertarianism needs.

But random quantum events are not obviously decisions.

Amplification

In principle, microscopic indeterminacy could be amplified into macroscopic neural differences.

That would create alternative outcomes.

It would not by itself create authorship.

Control Remains Central

The libertarian problem is therefore not:

How can the future branch?

Physics may already permit branching.

The hard problem is:

How can the agent control which branch becomes action without determining it?

Indeterministic Control

Some philosophers argue control need not be deterministic.

A skilled basketball player can intentionally attempt a difficult shot even when success is probabilistic.

The action remains hers.

Action vs Outcome

This analogy distinguishes:

• control over trying,
• control over outcome.

But free-will debates concern the selection of the trying itself.

So the analogy only goes partway.

Probabilistic Agency

We routinely control systems probabilistically.

A doctor chooses a treatment without guaranteeing success.

Control does not require certainty.

This shows probabilistic causation is compatible with some forms of agency.

Does It Solve the Ultimate Problem?

Not entirely.

The question is not whether probabilistic action can be controlled.

It is whether indeterminism adds the special freedom incompatibilists seek.

Explanatory Contrast

Compatibilist:

I chose this because of my reasons.

Libertarian:

I chose this because of my reasons, but those reasons did not fully determine the choice.

The second preserves openness at the cost of a harder explanatory gap.

Moral Responsibility

Libertarianism supports strong moral desert more naturally.

If the agent genuinely originates alternatives, praise and blame seem deeper.

This is one reason the view remains attractive.

The Intuitive Pull

Many people experience deliberation as:

the future is open.

I can go either way.

Libertarianism takes this phenomenology seriously.

But Phenomenology Is Not Proof

Feeling that a choice is open does not establish metaphysical indeterminism.

Introspection does not reveal complete causal structure.

The theory needs more than subjective impression.

The Scientific Problem

How could we experimentally distinguish:

• deterministic reasons-responsive decision,
• indeterministic agent-controlled decision?

This is extremely difficult.

Observed variability does not prove libertarian causation.

The Metaphysical Cost

Agent causation introduces a primitive causal category.

Event-causal libertarianism introduces indeterministic control.

Both pay theoretical costs.

The question is whether those costs are worth preserving strong freedom.

Compatibilist Challenge

Compatibilists say libertarianism solves a problem we do not need to solve.

Reasons-responsive self-control is already enough.

Adding indeterminism may only add luck.

Libertarian Challenge

Libertarians reply compatibilist freedom is merely sophisticated determination.

It does not capture the intuition that:

the agent could truly choose otherwise.

The disagreement concerns the concept of freedom itself.

The Philosophical Lesson

Libertarian free will attempts to combine three demanding conditions:

• alternative possibilities,
• authorship,
• rational control.

Indeterminism supplies openness.

It does not automatically supply agency.

The central challenge is explaining how a choice can be:

not determined

without being:

merely random.

The Next Question

That distinction deserves a full essay.

A coin flip is unpredictable.

But nobody calls the coin free.

Why not?

Because:

Randomness Is Not Freedom.