Perspective on Belief Systems

After reading The Dark Side of the Buddha, a thought occurred to me about the nature of belief systems. All belief systems are based on a perspective on reality, on its nature, direction, structure. Which of course is accounted for by the nature of this context: space, time, and entities in that space time. However, each perspective is based on a set of givens ( assumptions, presuppositions, axioms, ... ). Then these givens are generalized to all contexts and situations. Which of course simply cannot be because there is far too much diversity to be covered by a single lens. Take for example Buddhism. There is the notion of the four noble truths. This perspective takes as a given that there is suffering. However, there is not suffering all the time in all contexts. Similarly, one can take the basic perspective of any philosophy / religion and find the givens in it and also the problems with those givens in different contexts.