It is probably safe to say that all the changes of factual knowledge which have led to the relativity theory, resulting in a very great theoretical development, are completely trivial from any point of view except their relevance to the structure of a theoretical system. – Talcott Parsons

The hypothesis may be put forward, to be tested by the s subsequent investigation, that this development has been in large part a matter of the reciprocal interaction of new factual insights and knowledge on the one hand with changes in the theoretical system on the other. – Talcott Parsons

The implications of these considerations justify the statement that all empirically verifiable knowledge even the commonsense knowledge of everyday life – involves implicitly, if not explicitly, systematic theory in this sense. – Talcott Parsons