certainties

Certainties are propositions or beliefs held with complete confidence in their truth. They can refer to epistemic status—the justification for a belief—as well as a psychological state of certainty. People often distinguish certainties from probabilities or guesses, recognizing that high confidence does not always imply absolute truth.

In philosophy, certainty has driven debates about knowledge. Rationalist traditions seek indubitable foundations, as in Descartes’ method of doubt and the quest for a foundational certainty. In logic and mathematics, certainties are deductive necessities: conclusions that follow with logical necessity from established axioms or definitions. In empirical inquiry, certainty is more fragile, since evidence can be incomplete and theories provisional.

Critics argue that absolute certainty is rare or impossible across most domains. Skepticism challenges whether any belief can be beyond dispute. Human perception, memory, and language can mislead; even mathematical systems face limits. Gödel’s incompleteness theorems illustrate that no sufficiently powerful formal system can prove all truths within itself. Science treats theories as reliable models rather than final certainties, always open to revision in light of new evidence.

Certainty also appears in practical contexts, such as arithmetic truths or legal standards that require beyond reasonable doubt. Psychological certainty—how confident a person feels—may diverge from epistemic justification and can be influenced by bias, information quality, and context.

Related notions include probability, justification, belief, and knowledge. The study of certainties spans epistemology, philosophy of science, and cognitive psychology, highlighting that what counts as certain often depends on context, method, and criteria of justification.