The Gettier problem, in the field of epistemology, is a landmark philosophical problem with our understanding of knowledge. Attributed to American philosopher Edmund Gettier, Gettier-type counterexamples (called "Gettier-cases") challenged the long-held justified true belief (or JTB) account of knowledge. On the JTB account, knowledge is equivalent to justified true belief, and if all three conditions (justification, truth, and belief) are met of a given claim, then we have knowledge of that proposition. In his three-page 1963 paper, titled Is Justified True Belief Knowledge?, Gettier showed, by...