Free Will

Table of Contents

  1. Do People have Free Will?
  2. Big Picture Graphic
  3. Nature of Free Will
  4. Kinds of Determinism (and Probabilities)
    1. Classical Determinism
    2. Neural Determinism
    3. Psychological Determinism
    4. Quantum Probability
  5. Arguments for Free Will
    1. Self-Evidence
    2. Moral Responsibility
    3. Making a Virtue of Necessity
  6. Moral Responsibility and the Principle of Alternate Possibilities
  7. Sorites Argument Against Free Will

Do People have Free Will?

“The most contentious question of metaphysics, the most contentious science” (David Hume)

Big Picture Graphic

Nature of Free Will

  • Is Free Will the ability to:
    • Choose among alternatives?
    • Have done otherwise had you wanted, chosen, or tried to?
    • Have done otherwise under the same conditions?

View Nature of Free Will

Kinds of Determinism (and Probabilities)

Classical Determinism

Classical Determinism is the thesis that every event is determined by laws of nature and antecedent conditions.

View Classical Determinism

Neural Determinism

Neural Determinism is the view that free will is incompatible with the operation of the brain.

View Neural Determinism

Psychological Determinism

Psychological Determinism is the claim that human actions are determined by psychological laws, e.g. the Law of Strongest Motive.

View Psychological Determinism

Quantum Probability

Quantum Probability is the claim that free will is incompatible with the probabilities predicted by Quantum Mechanics.

View Quantum Probability

Arguments for Free Will

Self-Evidence
  • As a person deliberates what to do it’s self-evident to them they can choose any option under consideration.
    Moral Responsibility
    • People are morally responsible for some of their actions.
    • A person is morally responsible for an action only if they can act otherwise.
    • Therefore, people can sometimes act otherwise.
    Making a Virtue of Necessity
    • A rational person must be able to believe what’s rational to believe.
    • People are unable to believe they don’t have free will.
    • Therefore, it’s not rational to believe people don’t have free will.

    View Arguments for Free Will

    Moral Responsibility and the Principle of Alternate Possibilities

    The Principle of Alternate Possibilities (PAP) is that people are morally responsible only if they could have done otherwise.

    View Principle of Alternate Possibilities

    Sorites Argument Against Free Will

    • People believe they have categorical free will, that they could have done otherwise under conditions at the time.
    • Moral responsibility requires categorical free will.
    • Being morally responsible for their actions is important to people.
    • Thus, having categorical free will matters to people.
    • Both Neural Determinism and Quantum Probability are incompatible with categorical free will.
    • There is substantial evidence supporting both theories.
    • There is no compelling argument for categorical free will.
    • Hence there is substantial evidence that a belief that matters to people – that they could have done otherwise under the conditions at the time – is false.