This dissertation argues that the lack of agreement over the role of metaphor and analogy as rhetorical tools for the technical communicator is evidenced in technical communication textbooks. These textbooks are also used to introduce engineers and scientists to the concept of technical communication. The argument for metaphor is built by first examining theory drawn from rhetoric, philosophy of science, and literature studies. Then, the use of metaphor to describe cloning is examined as an instance of when the scientific community has failed to communicate what cloning is to a general public fearful that scientists are playing God. To broaden the problem, the early work in physics that sought to describe the structure of an atom is examined because it is an instance of when scientists gave up on analogy because mathematical models became easier to use as description. In this study, it is argued that the decision to forfeit the analogy drawn between the solar system and an atom was one that was cultural rather than based on the analogy's epistemological value. Attitudes toward metaphor in technical communication are discussed in greater detail by reviewing scholarly work in technical communication that focuses on the historical aspect of metaphor. Pertinent topics such as whether or not Thomas Sprat was correct in his interpretation of Francis Bacon as one who would advise scientists, and the technical communicator, to eschew metaphor are examined. The role of metaphor in the computer industry is reviewed in terms of how it has been discussed in the technical communication literature. Finally, how teachers of technical communication might teach students to use metaphor is considered. (Timothy Giles)