 The traditional analysis of knowledge, brought into contemporary discussion (and famously criticized) by Gettier (1963), takes propositional knowledge to be a species of belief—specifically, justified true belief. Most contemporary treatments of knowledge are modifications or qualifications of the traditional analysis and consequently also treat knowledge as a species of belief. (For a detailed treatment of this topic see the entry on the  analysis of knowledge.  For critique of the view that propositional knowledge entails belief, see Radford 1966; Murray, Sytsma, and Livengood 2013; Myers-Schulz and Schwitzgebel 2013)