Examining the phenomenon of so-called faultless disagreement, I make two central claims in my dissertation. Such disagreements are faultless because they concern what I call ‘basic evaluations.’ These evaluations are rooted in personal tastes and preferences and are therefore immune to any cognitive influence. The kinds of claims that give rise to faultless disagreement can thus be understood in non-cognitive terms. Moreover, they rationally require the adoption of an attitude of toleration: if there is no method of determining who has gotten things right, it is indefensible to reject a seemingly contradictory evaluation as mistaken.