 A fourth response is that there is no evidence that knowledge requires the sort of dispositions that epistemic situationism challenges and, moreover, that there is theoretical and empirical evidence that knowledge does not require such dispositions (Turri 2017). More specifically, according to this line of criticism, no serious argument has ever been provided that knowledge requires reliability; instead, philosophers have relied on weak explanatory arguments or, more commonly, simply assumed that knowledge requires reliability (Turri 2016a). Moreover, if knowledge is an achievement, then we should expect it to not require reliability, because no other achievement requires reliability (Turri 2015c). Additionally, recent empirical studies have shown that the ordinary concept of knowledge—which is the concept practitioners have claimed to be interested in—does not make reliability a necessary condition of knowledge (Turri 2016a). For instance, in cases of perceptual and memorial beliefs, people attribute knowledge at similarly high rates (~80%) regardless of whether the agent gets it right ten-percent of the time or ninety-percent of the time. Along with this line of criticism, researchers have offered an alternative theory of knowledge that allows for knowledge produced by even highly unreliable cognitive abilities or powers (Turri 2016a,c).