An excellent late 19th-century philosophical study of scientific method and logic, covering the mathematics of science in the principles of number, induction, propositions, etc, referencing major figures in western philosophy and science from Kant to Leibniz to Kepler to Herschel. In this famed work W. Stanley Jevons defines the laws of logical thought as governed primarily by inductive inquiry and deductive reasoning, supported with experimental verification. The cover depicts the famed Logical Machine devised by Jevons, which earned much acclaim at its exhibition at the Royal Society in 1870. It actually solved problems with superhuman speed and accuracy, and some of its features can be traced in modern computer design.