Epistemology
How can belief become knowledge, and what gives inquiry authority over mere opinion?
Reason, innate structure, or intellectual intuition can ground knowledge beyond sensory experience.
Experience is the primary source and test of ideas, concepts, and justified belief.
Knowledge requires both sensory givenness and the mind's a priori forms of organization.
Claims to knowledge are continually tested by doubt, disagreement, and the limits of justification.
Knowing is tied to inquiry, practice, consequences, and the correction of belief in experience.
Knowledge is one of the map’s central organizing problems because nearly every school must say how philosophy can claim authority. Rationalists, empiricists, skeptics, Kantians, and pragmatists disagree over whether certainty, experience, structure, practice, or disciplined doubt carries the burden.
The problem also links outward: to causality when explaining the world, to universals when forming concepts, and to selfhood when asking who knows.