Fallibilism is the idea that it is impossible to know something for sure, or at least that all claims to know could, in principle, be wrong. It is most often linked to Charles Sanders Peirce, who used it to argue against foundationalism as a formal doctrine. Fallibilism, unlike skepticism, doesn’t mean that people must give up what they know.

People don’t have to have logically conclusive reasons for what they know. Instead, it’s an admission that, since empirical knowledge can be changed by more observations, all knowledge, except for axiomatically correct knowledge (like math and logic), is always changing.