If we consider a relation of things through relativism, there is no way we can ever know the truth. On the other side, the kind of knowledge we have is subjective. We feel things at a different intensity, but it does not mean that the knowledge becomes singular. We all know and understand the concepts without confusing them, for example: we all know what “hot” and “cold” means; there is a variety of intensity in the perception of the word, but it cannot be confused with another concept like “light” or “pudding”.
We can measure reality in relation to our point of view and that this fact is as close as anyone can get to the truth. If realism was the only way to know things we couldn’t be able to speak of what we feel. We could not speak of what humans are, and how to treat them; everything would be reduced as animals perceive, to gain their own benefit or harm; to react to everything that is around us. Men would become an object and not an intelligent being capable to perfect himself by appreciating beauty, knowing the truth and wanting good. If knowledge reduces a man to what is relative to him, he will lose the most important trait that constitutes him: to transcend and be happy.