the modern , restricted , sense of the word as a branch of learning based on observation and tested truths , arranged in an orderly system , was first recorded in isaac watts logic ( 1725 ) , and had by then developed from meaning a particular branch of knowledgesuch as logic , grammar , rhetoric , arithmetic , geometry , astronomyas distinguished from art ( which , in many views is yet another path to finding out how things are ) , into wearing its broader , current meaning .