Determinism is the idea that everything that happens, including all human actions, is completely determined by prior events. There is only one possible future, and it is completely predictable in principle.

Determinism is sometimes confused with causality, the idea that all events have causes. Some events may be undetermined by prior events. They are called indeterminate, sometimes known as a "causa sui" or self-caused event. But they may in turn be the causes for following events that would therefore not be predictable from conditions before the uncaused event. We call this "soft" causality. Events are caused, but not predictable or determined.

Uncaused events are said to break the "causal chain" of events back to a primordial cause. Aristotle's "accidents" and Epicurus' "swerve" were such uncaused causes.

There are many determinisms, depending on what pre-conditions are considered to be determinative of an event or action. We identify twelve determinisms below.

But there is only one irreducible freedom, based on a genuine randomness that provides for a world with breaks in the causal chain. Quantum mechanics is the fundamental source for indeterminacy and unpredictability in the physical, biological, and human worlds. It generates the Agenda for our Micro Mind in the Cogito model for Free Will.

Philosophers and religious thinkers become quite perplexed when considering the basic conflict between such an irreducible freedom and their own particular determinism.

Even some philosophers who accept the idea of human freedom are uncomfortable with the non-intuitive physics underlying quantum mechanics and the uncertainty principle. True chance is problematic, even for many scientists, including those like Planck and Einstein, who discovered the quantum world.

Behavioral Determinism assumes that our actions are reflex reactions developed in us by environmental conditioning. This is the Nurture side of the famous Nature/Nurture debate - note that both are determinisms.

Biological Determinism finds causes for our actions in our genetic makeup. This is the Nature side of the Nature/Nurture debate - both sides are determinisms.

Causal Determinism finds that every event has an antecedent cause in the infinite causal chain going back to Aristotle's Prime Mover. There is nothing uncaused or self-caused (causa sui).

Historical Determinism is the dialectical idealism of Hegel or the dialectical materialism of Marx that govern the course of history.

Logical Determinism reasons that a statement about a future event happening is either true or it is not. If the statement is true, logical certainty necessitates the event (Aristotle's Sea Battle).

Language Determinism claims that our language determines the things we can think and say. The Sapir-Whorf hypothesis finds speech in a language community highly predictable.

Mechanical Determinism explains man as a machine. If Newton's Laws of Classical Mechanics govern the workings of the planets, stars, and galaxies, surely they govern man the same way.

Physical Determinism extends the laws of physics to every atom in the human mind and assumes the mind will someday be perfectly predictable once enough measurements are made.

Psychological Determinism finds events in our childhood that are controlling our actions and mental states today.

Religious Determinism is the logical consequence of the presumed omniscience of God. God has foreknowledge of all events. All times are equally present to His eye (totem simul).

Fatalism is the simple idea that everything is fated to happen, so that humans have no control over their future.

Compatibilism is the idea that Free Will is compatible with Determinism. Compatibilists believe that as long as our Mind is one cause in the causal chain that we can be responsible for our actions, which is reasonable. But they think every cause, including our decisions, are pre-determined. Compatibilists are Determinists.

Some of these determinisms (behavioral, biological, historical-economic, language, psychological, and religious) have modest to significant evidence that they do limit human freedom. But others are merely dogmas of determinism, believed for the simple reason that they eliminate random chance in the universe.

Chance is anathema to most philosophers.