It is a method that does not use hard science (at least not directly) to arrive at a result but you are allowed to infer on the basis of assumptions, previous experience in similar situations, a change of point of view one less Orthodox; and not necessarily reached a correct result, but sometimes only one approach, something that serves home need. It comes from the Greek x3B5; x3C5; x3C1; x3B9; x3C3; x3BA; x3B5; x3B9; x3BD; (euriskein "find, invent").