Sentence:  Social invention did not have to await social <WSD>theory</WSD> any more than use of the warmth of a fire had to await Lavoisier or the buoyant protection of a boat the formulations of Archimedes . 
Meaning of the word marked with <WSD> tags:  a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena