selfevidence

Self-evidence is a quality attributed to beliefs, propositions, or ideas that are thought to be true in themselves, without requiring external proof or empirical observation. A self-evident claim is supposed to be evident to the mind through its content, meaning, or logical form, or to be immediately grasped by intuition. The term is used in epistemology, logic, and mathematics to distinguish foundational or basic commitments from those that require demonstration or evidence.

In philosophical tradition, self-evidence is often linked to foundationalism, which seeks basic beliefs that justify other knowledge claims. Certain propositions are commonly cited as self-evident in various cultures or systems, such as the law of non-contradiction (A cannot be both B and not-B at the same time) or, in rationalist thought, clear and distinct ideas that allegedly disclose themselves to the mind. Descartes popularized the idea that some truths are self-evident to the rational intellect, with famous examples like “I think, therefore I am.” In mathematics and formal logic, axioms or primitive notions are sometimes treated as self-evident starting points chosen for their apparent necessity and coherence rather than for external verification.

Self-evidence is controversial because it is, by its nature, subject to disagreement and interpretation. Critics argue that what seems self-evident can be a result of conceptual frameworks, linguistic conventions, or cognitive biases, and may not withstand scrutiny under new theories or evidence. In contemporary epistemology, self-evidence is often distinguished from merely intuitive or prima facie plausibility, and its role in justification is viewed as one option among several in explaining how beliefs are supported.