Expert: date=October 2008

Determinism is the philosophical proposition that every event, including human cognition and behavior, decision and action, is causally determined by an unbroken chain of prior occurrences. Numerous historical debates, many varieties and philosophical positions on the subject of determinism exist from traditions throughout the world.

Philosophy of determinism

It is a popular belief that determinism necessarily entails that humanity or individual humans have no influence on the future and its events (a position known as fatalism); however, determinists believe that the level to which human beings have influence over their future is itself dependent on present and past. Causal determinism is associated with, and relies upon, the ideas of materialism and causality. Some of the main philosophers who have dealt with this issue are Steven M. Cahn, Marcus Aurelius, Omar Khayyám, Thomas Hobbes, Baruch Spinoza, Gottfried Leibniz, David Hume, Baron d'Holbach (Paul Heinrich Dietrich), Pierre-Simon Laplace, Arthur Schopenhauer, William James, Friedrich Nietzsche, Albert Einstein, Niels Bohr, and, more recently, John Searle, Ted Honderich, and Daniel Dennett.

Mecca Chiesa notes that the probabilistic or selectionistic determinism of B.F. Skinner comprised a wholly separate conception of determinism that was not mechanistic at all. A mechanistic determinism would assume that every event has an unbroken chain of prior occurrences, but a selectionistic or probabilistic model does not.

The nature of determinism

The exact meaning of the term determinism has historically been subject to rigorous scrutiny and several interpretations. Some people, called Incompatibilists, view determinism and free will as mutually exclusive. The belief that free will is an illusion is known as Hard Determinism. Others, labeled Compatibilists, (or Soft Determinists) believe that the two ideas can be coherently reconciled. Incompatibilists who accept free will but reject determinism are called Philosophical Libertarians — not to be confused with Political Libertarians. Some feel it refers to the metaphysical truth of independent agency, whereas others simply define it as the feeling of agency that humans experience when they act. Many will agree that determinism is the theory that human choices and actions can be determined from external causes; but free will is the theory that human choices and actions are determined by internal causes: that an individual is the prime mover of his life.

Ted Honderich, in his book How Free Are You? - The Determinism Problem gives the following summary of the theory of determinism:

In its central part, determinism is the theory that our choices and decisions and what gives rise to them are effects. What the theory comes to therefore depends on what effects are taken to be... 1t is effects that seem fundamental to the subject of determinism and how it affects our lives.