ABSTRACT
Historians of logic presume that the development of conceptions of inference began with the work of George Boole, so that they tend to neglect earlier accounts of the nature of inference. In the seventeenth century, for example, Descartes’ account involved a theory that inference must be grasped in an intuitus; a conception of humans as machines; and a belief that God freely creates eternal truths. From the time of Descartes there have been a number of attempts to construct machines that perform computations, a prime example being the work of Jevons’s contemporary, Charles Babbage. Barrels, however, were regarded as an integral part of the machine they were controlling rather than as the means by which a general-purpose machine was set up to do a specific series of actions. Later on, from the 1890s, the sequencing information was held on rolls of tape, as in early versions of the pianola or player piano.
