Lecture Notes by Christopher Lay

Los Angeles Pierce College

Department of History, Philosophy, and Sociology

 

 

 

 

Mathew Van Cleave's 2016 Introduction to Logic and Critical Thinking

 

https://open.umn.edu/opentextbooks/BookDetail.aspx?bookId=457

 

 

 

 

Chapter 4 "Informal fallacies", § 1 "Formal vs. Informal Fallacies"

"A fallacy is simply a mistake in reasoning." 

 

"Some fallacies are formal and some are informal." 

 

(Note that the introduction to this chapter makes references to parts of the text we haven't covered, e.g. formal logic which is needed to understand formal fallacies.  We'll cover those parts later.)

 

 

 

 

 

 

 

 

 

 

From the next sub-§: With "an informal fallacy ... we have to rely on our understanding of the meanings of the words or concepts involved ... ." 

 

With formal fallacies (as we'll see later in the course), we can "simply ... identify the fallacy from its form."