The world reveals itself to man as a multiplicity, as the sum of simple unitary elements, of which man himself is the most important as a being among other beings. For the time being, we consider this aspect of the world as given, therefore real, and since we do not develop it consciously, but find it made as such, we call it perception. We perceive ourselves in this world of perceptions, too. Yet, this self-perception would simply be like any other if it did not generate something that can connect perceptions in general, thus creating a link between the entirety of all these perceptions and our self. This something which springs out of self-perception is not mere perception any longer. Nor is it something that we can take for granted, as reality is. That is why reason is, first and foremost, expressed in the inner reality; but it is not purely subjective, since the self becomes a subject only with the help of reason. This reasonable way of relating to ourselves is an essential determinant of our personalities. But with it we can only exist on a purely idealistic level. If we call such a connection based on reason, 'knowledge', and if we define the state of knowing as the wellbeing based on the same connection, then we should consider ourselves as exclusively knowledgeable and real beings - supposing the assumption above proved to be true. Yet, in reality, the assumption does not prove to be true. We do not solely project our perceptions to ourselves ideally, through concepts, we also consider feelings, since we are creatures whose life contents is purely conceptual. The realist sees in feelings a more realistic life of the personality than in the purely idealistic element of controlling reality through reason. As, according to the fundamental principle of reality, everything that can be perceived is real, the feeling is proof of the reality of our own personalities.