The Commens Dictionary
Quote from ‘Grand Logic 1893: Division II. Methodology. Chapter XV. Breadth and Depth’
An imaginary increase of information is an assumption or supposition; but the former word is preferable. An increase of information by induction, hypothesis, or analogy, is a presumption. (A legal presumption is a presumption which follows an accepted rule of the courts, irrespective of the dictates of good sense.) A very weak presumption is a guess. A presumption opposed to direct testimony is a conjecture, or, if weak, a surmise.