Unknowability

Unknowability is the quality or state of being unknowable, either in principle or in practice. In philosophy and related fields, unknowability can be categorized as either ontological (absolute) or epistemic (relative). Ontological unknowability refers to propositions or aspects of reality that are beyond the possibility of any knowing subject or method. Epistemic unknowability refers to limits encountered by particular agents, cognitive frameworks, or technologies when evidence or inference cannot fully determine truth.

Epistemic unknowability arises from limitations such as insufficient evidence, computational constraints, or explanatory gaps. It is a common theme in skepticism and in discussions of scientific limits. Examples include asymptotic limits in formal systems (Gödel's incompleteness theorem), limits of measurement and observation (Heisenberg uncertainty principle), and quantum indeterminacy where certain properties do not have definite values until measured.

Practical unknowability results from complexity, chaos, or data scarcity, producing situations where reliable knowledge cannot be obtained within resource constraints.

Debates surround whether unknowability is a genuine barrier or a temporary state that science and inquiry can eventually overcome. Some traditions treat unknowability as a permanent feature of reality, while others view it as a methodological limit that can be reduced with new theories or technologies.

In information theory and philosophy of science, unknowability helps delineate what can be known, what is merely uncertain, and what lies beyond the reach of current methods. See also epistemology, uncertainty principle, Gödel's incompleteness theorem, and Kant's noumenon.