Determinism
Determinism is the metaphysical view that all events within the universe can occur only in one possible way. Deterministic theories throughout the history of philosophy have developed from diverse and sometimes overlapping motives and considerations. Like eternalism, determinism focuses on particular events rather than the future as a concept. Determinism is often contrasted with free will, although some philosophers argue that the two are compatible. The antonym of determinism is indeterminism, the view that events are not deterministically caused.
Historically, debates about determinism have involved many philosophical positions and given rise to multiple varieties or interpretations of determinism. One topic of debate concerns the scope of determined systems. Some philosophers have maintained that the entire universe is a single determinate system, while others identify more limited determinate systems. Another common debate topic is whether determinism and free will can coexist; compatibilism and incompatibilism represent the opposing sides of this debate.
Determinism should not be confused with the self-determination of human actions by reasons, motives, and desires. Determinism is about interactions which affect cognitive processes in people's lives. It is about the cause and the result of what people have done. Cause and result are always bound together in cognitive processes. It assumes that if an observer has sufficient information about an object or human being, then such an observer might be able to predict every consequent move of that object or human being. Determinism rarely requires that perfect prediction be practically possible.
Causal determinism posits that every event results from preceding events and natural laws, while nomological determinism emphasizes the predictability of the future from past and present states. Necessitarianism claims only one possible world exists, and predeterminism suggests events are fixed in advance, sometimes biologically or genetically. Fatalism and theological determinism attribute outcomes to fate or divine omniscience, whereas adequate determinism and interpretations of quantum mechanics explore probabilistic or emergent constraints on macroscopic phenomena. Philosophical varieties extend to human behavior, including biological, psychological, social, and cultural determinism, as well as structural determinism, which highlights systemic constraints. Historically, determinism appears in both Western traditions, from the Presocratics and Stoics to Newtonian mechanics, and Eastern thought, including karma, Ājīvika fatalism, and Buddhist dependent origination. Modern science recognizes deterministic models in classical physics and complex generative processes, while quantum mechanics introduces probabilistic and debated interpretations.
Varieties
Determinism may commonly refer to any of the following viewpoints:Causal
Causal determinism, sometimes synonymous with historical determinism, is "the idea that every event is necessitated by antecedent events and conditions together with the laws of nature." However, it is a broad enough term to consider that:...One's deliberations, choices, and actions will often be necessary links in the causal chain that brings something about. In other words, even though our deliberations, choices, and actions are themselves determined like everything else, it is still the case, according to causal determinism, that the occurrence or existence of yet other things depends upon our deliberating, choosing and acting in a certain way.Causal determinism proposes that there is an unbroken chain of prior occurrences stretching back to the origin of the universe. The relation between events and the origin of the universe may not be specified. Causal determinists believe that there is nothing in the universe that has no cause or is self-caused.
Causal determinism has also been considered more generally as the idea that everything that happens or exists is caused by antecedent conditions. In the case of nomological determinism, these conditions are considered events also, implying that the future is determined completely by preceding events—a combination of prior states of the universe and the laws of nature. These conditions can also be considered metaphysical in origin.
Nomological
Nomological determinism is the most common form of causal determinism and is generally synonymous with physical determinism. This is the notion that the past and the present dictate the future entirely and necessarily by rigid natural laws and that every occurrence inevitably results from prior events. Nomological determinism is sometimes illustrated by the thought experiment of Laplace's demon. Laplace posited that an omniscient observer, knowing with infinite precision all the positions and velocities of every particle in the universe, could predict the future entirely. Ernest Nagel viewed determinism in terms of a physical state, declaring a theory to be deterministic if it predicts a state at other times uniquely from values at one given time.Necessitarianism
is a metaphysical principle that denies all mere possibility and maintains that there is only one possible way for the world to exist. Leucippus claimed there are no uncaused events and that everything occurs for a reason and by necessity.Predeterminism
is the idea that all events are determined in advance. The concept is often argued by invoking causal determinism, implying that there is an unbroken chain of prior occurrences stretching back to the origin of the universe. In the case of predeterminism, this chain of events has been pre-established, and human actions cannot interfere with the outcomes of this pre-established chain.Predeterminism can be categorized as a specific type of determinism when it is used to mean pre-established causal determinism. It can also be used interchangeably with causal determinism—in the context of its capacity to determine future events. However, predeterminism is often considered as independent of causal determinism.
Biological
The term predeterminism is also frequently used in the context of biology and heredity, in which case it represents a form of biological determinism, sometimes called genetic determinism. Biological determinism is the idea that all human behaviors, beliefs, and desires are fixed by human genetic nature.Friedrich Nietzsche explained that human beings are "determined" by their bodies and are subject to its passions, impulses, and instincts.
Fatalism
is normally distinguished from determinism, as a form of teleological determinism. Fatalism is the idea that everything is fated to happen, resulting in humans having no control over their future. Fate has arbitrary power, and does not necessarily follow any causal or deterministic laws. Types of fatalism include hard theological determinism and the idea of predestination, where there is a God who determines all that humans will do. This may be accomplished through either foreknowledge of their actions, achieved through omniscience or by predetermining their actions.Theological
is a form of determinism that holds that all events that happen are either preordained to happen by a monotheistic deity, or are destined to occur given its omniscience. Two forms of theological determinism exist, referred to as strong and weak theological determinism.Strong theological determinism is based on the concept of a creator deity dictating all events in history: "everything that happens has been predestined to happen by an omniscient, omnipotent divinity."
Weak theological determinism is based on the concept of divine foreknowledge—"because God's omniscience is perfect, what God knows about the future will inevitably happen, which means, consequently, that the future is already fixed." There exist slight variations on this categorization, however. Some claim either that theological determinism requires predestination of all events and outcomes by the divinity—i.e., they do not classify the weaker version as theological determinism unless libertarian free will is assumed to be denied as a consequence—or that the weaker version does not constitute theological determinism at all.
With respect to free will, "theological determinism is the thesis that God exists and has infallible knowledge of all true propositions including propositions about our future actions", more minimal criteria designed to encapsulate all forms of theological determinism.
Theological determinism can also be seen as a form of causal determinism, in which the antecedent conditions are the nature and will of God. Some have asserted that Augustine of Hippo introduced theological determinism into Christianity in 412 CE, whereas all prior Christian authors supported free will against Stoic and Gnostic determinism. However, there are many Biblical passages that seem to support the idea of some kind of theological determinism.
Adequate
Adequate determinism is the idea, because of quantum decoherence, that quantum indeterminacy can be ignored for most macroscopic events. Random quantum events "average out" in the limit of large numbers of particles. While there are specific examples of these random events magnified to macro levels, such as Geiger counters, they are still insignificant in the context of free will.Determined probability
explained that the microscopic world of quantum mechanics is one of determined probabilities. That is, nature is not governed by laws that determine the future with certainty but by laws that determine the probability of various futures.Many-worlds interpretation
The many-worlds interpretation of quantum mechanics accepts the linear causal sets of sequential events with adequate consistency yet also suggests constant forking of causal chains that can in principle be globally deterministic. Meaning the causal set of events leading to the present are all valid yet appear as a singular linear time stream within a much broader unseen conic probability field of other outcomes that "split off" from the locally observed timeline. Under this model causal sets are still "consistent" yet not exclusive to singular iterated outcomes.The interpretation sidesteps the exclusive retrospective causal chain problem of "could not have done otherwise" by suggesting "the other outcome does exist" in a set of parallel states of the universe that split off in any interacting event. This interpretation is sometimes described with the example of agent-based choices.