indeterminacy

Indeterminacy is the property of a system, statement, or process in which the outcome, value, or truth cannot be determined with certainty from the available information or governing rules. It can arise from incomplete knowledge (epistemic indeterminacy), from intrinsic randomness (ontic indeterminacy), or from ambiguous or vague criteria (linguistic indeterminacy).

In philosophy and logic, indeterminacy appears in debates over vagueness, meaning, and reference. The boundaries of categories may be fuzzy, and some statements lack definite truth conditions. In decision theory and ethics, indeterminacy can reflect conflicting principles or uncertainty about consequences.

In physics, quantum indeterminacy denotes inherent probabilistic behavior: properties such as position and momentum do not possess exact values until measured. The Heisenberg uncertainty principle formalizes this limit. In classical dynamics, chaotic systems exhibit practical indeterminacy: tiny changes in initial conditions yield widely divergent outcomes, even if the laws are deterministic.

In mathematics, indeterminacy includes indeterminate forms like 0/0 and ∞−∞, which require limiting processes to resolve. In computation, nondeterminism and undecidability describe limits of algorithms and models.

Across disciplines, indeterminacy is managed with probability, statistics, and uncertainty quantification, and it informs interpretations of prediction, measurement, and model adequacy. Distinctions are often drawn between epistemic indeterminacy (knowledge-based) and ontological indeterminacy (nature-based).