  At the end of Book V (474bff), Socrates begins his defense of the rule of the philosopher by contrasting his epistemological condition with that of a group of sightlovers. The philosopher, who accepts that there are Forms, e.g., Beauty Itself, has knowledge. The sightlover, who denies that there is Beauty Itself but rather insists that there are just the many (different) beautiful plays, paintings and such, lacks knowledge. He has only belief. In support of this contention, Socrates distinguishes three different kinds of mental states or capacities and three generic ‘objects’ for these capacities. Knowledge is set over ‘what completely is’; ignorance is set over ‘what completely is not’; and, belief, being intermediate between knowledge and ignorance, is set over what is intermediate between the other two generic objects, namely ‘what is and is not’. Capacities are distinguished, Socrates contends, by two criteria: 1) difference in objects; and 2) difference in what they do (with/to their objects). Examples of 1) include colors and sounds, and of course what completely is and what is and is not. The second criterion is seemingly satisfied by the difference between being true versus being true and false. Thus, knowledge is always true, whereas belief admits of both truth and falsehood.