Computers were needed to apply finance theory's models to trading. They also were needed to test the models against market data. As will be discussed in chapter 4, the results of those tests were by no means always positive, but as in analogous cases in the natural sciences (Harvey 1981) the very fact of finance theory's testability added to its credibility. It also helped the field to grow by creating roles in financial economics for those whose skills were primarily empirical rather than theoretical. Without computers, testing would have been very laborious if not impossible.

Donald MacKenzie, An Engine, Not a Camera, loc. 43