Since Aristotelian logic was the standard logic studied until the 19th Century, it could reasonably be claimed that connexive logic was the accepted school of thought among logicians for most of Western history. (Of course, logicians were not necessarily aware of belonging to the connexivist school.) However, in the 19th Century Boolean syllogisms, and a propositional logic based on truth-functions, became the standard. Since then, relatively few logicians have subscribed to connexivism. These few include E. J. Nelson and P. F. Strawson.