Gadamer claims that text understanding ins dependents on the perception of the audience from the text and association of semantic horizon and questioner mind of him. Yet, because of continuous changes in mental status of audience affected by historicity and being surrounded by presuppositions, the accurate and absolute awareness is impossible and misunderstanding is common. Also basically there is no absolute and abidingly true knowledge. The basis of Gadamer's assertion is presuppositions' uncontrollability or the mental processes of audience. This happens when cognitive psychology which has the most shared area with epistemology and hermeneutics, preferability , noting the process of realities, including text, while agreeing with existence of difficulties and challenges against understanding, cognitive psychology introduces factors and methods to control them and also presents the possibility of "Attention Preferability" in consciousness area.