10.4.2 Logos (Logical Appeal)
When you use reasons and arguments, backed up by facts and logic, to make your case, you are using logical appeals. Most writers easily understand the importance of reliable evidence in a persuasive document, but logical appeals extend to the structure of one’s argument. How you explain your evidence and its relationships to other claims and evidence is just as important a logical appeal as the information itself. In academic and technical communication, logos is the preferred method of persuasion.
Depending on the characteristics of the audience, including the audience’s predisposition to the topic and the persuasive objective of the speech, the message will use either an inductive or deductive strategy. Inductive reasoning presents facts or observations as the basis for making generalized statements. In deductive reasoning, we start with two or more factual statements and then draw a conclusion. Inductive reasoning may be understood as specific to general, whereas deductive reasoning is understood as general to specific. For example, in inductive reasoning, if you have had three bosses from a different generation that often struggled with technology, you now conclude that all members of that generation have challenges with technology. In deductive reasoning, a boss knows that a certain college program trains students to be proficient in a type of software. The boss might, therefore, hire a graduate of that program thinking that the graduate must also be proficient in that software.
This section is adapted from Informative and Persuasive Presentations by Jordan Smith available at Communication@Work – Simple Book Publishing licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.
Resources
Inductive & Deductive Reasoning. Khan Academy. https://www.khanacademy.org/math/algebra-home/alg-series-and-induction/alg-deductive-and-inductive-reasoning/v/deductive-reasoning-1 . The video is licensed under a Creative Commons Attribution–NonCommercial ShareAlike 4.0 International License, except where otherwise noted.
