Modeling Human–System Interaction

4 FORMS OF REPRESENTATION

VERBAL MODELS

Most of what can be called models are expressed in words only. Historians, philosophers, theologians, newspaper columnists, sportswriters all use words in print media to express their beliefs about how some things or events are structured or relate to other things or events. Some of these can be called scientific models because they explicate concisely the structure or function of some things or events. In the most general case, novelists, poets, and lyricists are verbal connotative modelers, but we choose to exclude those models because they do not intend to denotate the explicit truth.

In the following, for example, are Charles Darwin’s (1859) own words in On the Origin of Species that I have taken to be a summary explanation of his theory of natural selection, more commonly known as the theory of evolution. Of course, he wrote many more words of explanation in that famous work. But these words do exemplify what could be called a verbal scientific model.

Evolution by natural selection is a process that is inferred from three facts about populations: 1) more offspring are produced than can possibly survive; 2) traits vary among individuals, leading to differential rates of survival and reproduction; and 3) trait differences are heritable. Thus, when members of a population die they are replaced by the progeny of parents that were better adapted to survive and reproduce in the environment in which natural selection took place. ...