A Practical Study of Argument
Chapter 6: Supplementary Material
Relevance: The “R” Condition
After completing this unit of the textbook, you should be able to:
Demonstrate your understanding of relevance in the process of assessing
Demonstrate your ability to distinguish between positive relevance, negative
relevance, and irrelevance.
Demonstrate your ability to apply the R condition to the various argument types.
Demonstrate your ability to identify when arguments commit fallacies.
Relevance is an important concept but also a difficult and elusive one. It is important to
keep in mind as we work through this chapter that relevance must be distinguished from
sufficiency of grounds. When we talk about relevance, in general, what we have in mind
is simply premises which provide at least some evidence either for or against a
conclusion. So the emphasis will be on premises providing
reason to believe the
conclusion. This is independent of whether or not they provide
believe the conclusion.
When disputes arise about whether or not X is relevant to Y, remember that you need to
give reasons in support of their judgments about that matter, i.e. 'X is positively relevant
...' or 'X is not positively relevant to Y
Statement A is positively relevant to statement B if and only if the truth of A
counts in favor of the truth of B.
Premises are positively relevant to their conclusion when, if true, they provide
some reason to believe that the conclusion is true.
When there is positive relevance, one statement supports another.
Notice that this does not say that A is true, nor does it say that is a complete proof
of B. It merely says that
A is true, it is
When dealing with arguments, this is the condition that we want to find.
Statement A: Students who eat regularly at the college cafeteria have higher
incidences of intestinal distress than students who do not.
Statement B: Food prepared at the college cafeteria is harmful to student health.
Statement A is negatively relevant to statement B if and only if the truth of A
counts against the truth of B.
Premises are negatively relevant to their conclusion when, if true, they provide
some reason to think that the conclusion is false.
When there is negative relevance, one statement undermines another.