All knowledge in any area of study is limited or constrained by the assumptions of a given social (involving people) temporal (point in time) context. The boundaries of what is known is composed of the fundamental, often implicit, assumptions that are made about "how the world really is" until these boundaries change. These boundaries are in a sense permeable (open to new information) and malleable (can change in various ways as a result of that information). As information is accessed or revealed through experimentation, serendipity, etc., new boundaries emerge.
thoughts?