replacement to traditional epistemology. Jaegwon Kim, another critic of naturalized epistemology, further articulates the difficulty of removing the normative component. He notes that modern epistemology has been dominated by the concepts of justification and reliability. Kim explains that epistemology and knowledge are nearly eliminated in their common sense meanings without normative concepts such as these. These concepts are meant to engender the question "What conditions must a belief meet if we are justified in accepting it as true?". That is to say, what are the necessary criteria by which a particular belief can be declared as "true" (or, should it fail to meet these criteria, can we rightly infer its falsity)? This notion of truth rests solely on the conception and application of the criteria which are set forth in traditional and modern theories of epistemology. Kim adds to this claim by explaining how the idea of "justification" is the only notion (among "belief" and "truth") which is the defining characteristic of an epistemological study. To remove this aspect is to alter the very meaning and goal of epistemology, whereby we are no longer discussing the study and acquisition of knowledge. Justification is what makes knowledge valuable and normative; without it what can rightly be said to be true or false? We are left with only descriptions of the processes by which we arrive at a belief. Kim realizes that Quine is moving epistemology into the realm of psychology, where Quine's main interest is based on the sensory input–output relationship of an individual. This account can never establish an affirmable statement which can lead us to truth, since all statements without the normative are purely descriptive (which can never amount to knowledge). The vulgar allowance of any statement without discrimination as scientifically valid, though not true, makes Quine's theory difficult to accept under any epistemic theory which requires truth as the object of knowledge. As a result of these objections and others like them, most, including Quine in his later writings, have agreed that naturalized epistemology as a replacement may be too strong of a view. However, these objections have helped shape rather than eliminate naturalized epistemology. One product of these objections is cooperative naturalism which holds that empirical results are essential and useful to epistemology. That is, while traditional epistemology cannot be eliminated, neither can it succeed in its investigation of knowledge without empirical results from the natural sciences.