The Architecture and Engineering of Digital Computer Computers, Vol. 1

Computer science is a blend of engineering and mathematics. Being com­ paratively new, the field has not settled down to a definite mixture of science and engineering, but still contains large parts of both technology and art. Many computer scientists are trying to make computer science into a branch of mathematics, or to at least closely resemble mathematics. This approach tends to emphasize Turing machines, abstract linguistics, etc. Unfortunately these abstract models are often about as relevant to the real world as the mathematical theorem that you can't trisect an angle with ruler and compass-it is true, but we have protractors and marks on our rulers, so that practically we trisect angles every day. Against the mathematical approach are the hard facts of life: the com­ puter is a real, physical machine; it is often very eXpensive and hence the reality of economics enters; the machine is often a large collection of various parts whose working together must be controlled properly; and finally the whole exists to be used by humans in their work and not merely to be admired. Of necessity, these and many other related aspects are ignored in the mathe­ matical models. At the other extreme are the hard-nosed engineers who often become trapped in the crises, details, and day-to-day operation of the com­ puting center. They tend to adopt a strictly experimental, pragmatic approach.