The Gettier problem is considered a problem in modern
epistemology or
first-order logic, issuing from
counter-examples to the definition of knowledge as justified true belief, and dealing extensively with the concept of justified true belief (JTB), and the scope of the concept of JTB, as well as those attacks upon JTB which Gettier
exemplars introduce. The problem owes its name to a three-page paper published in 1963, by
Edmund Gettier, called "Is Justified True Belief Knowledge?", in which Gettier argues that this is not necessarily the case. Many or most
analytic philosophers would wish to be able to hold to what is known as the JTB account of knowledge: the claim that knowledge can be conceptually analyzed as
justified true belief — which is to say that the meaning of sentences such as "Smith knows that it rained today" can be given with the following set of
necessary and jointly sufficient conditions: A subject <var>S</var> knows that a proposition <var>P</var> is true
if, and only if:<var>P</var> is true<var>S</var> believes that <var>P </var> is true, and<var>S</var> is
justified in believing that <var>P</var>
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