The study begins with the development of the nature and character of fifteenth century Italian humanism. It then proceeds to delineate the humanist methodological approach to three key areas; rhetoric, grammar, and historical criticism. Having thus laid this necessary foundation, the work examines selected portions of the debates of the council with regard to each of the three key areas, in order to ascertain whether or not a humanistic approach was utilized by the Latin participants in their argumentations. This investigation concludes that the Latin advocates of the council did indeed employ humanist methodology in both the preparation and presentation of their arguments in the debates. Therefore, such evidence strongly suggests that an appreciation and acceptance of the humanist approach to rhetoric, grammar, and textual criticism existed in the church in the early decades of the fifteenth century.