Belief forms the greatest part of our perceptions.
The projection comes from our very being whose basis is formed by belief. Our beliefs are first formed within us unconsciously and become so central to our being that we use them to form criteria by which to judge all information. Even Descartes seemed to use his method to confirm his original convictions. Many of our beliefs are universal because they are based on the experiences of all human beings. However, many are unique to certain cultures and thus create barriers to cross-cultural understanding.