Identifying arguments (Dr. Van Cleave)

By Matthew Van Cleave

The best way to identify whether an argument is present is to ask whether there is a statement that someone is trying to establish as true by basing it on some other statement.  If so, then there is an argument present.  If not, then there isn’t.  Another thing that can help in identifying arguments is knowing certain key words or phrases that are premise indicators or conclusion indicators.  For example, recall Sally’s abortion argument:

The word “because” here is a premise indicator.  That is, “because” indicates that what follows is a reason for thinking that abortion is morally wrong.  Here is another example:

In this example, the word “since” is a premise indicator because what follows it is a statement that is clearly intended to be a reason for thinking that the student plagiarized (i.e., a premise).  Notice that in these two cases, the premise indicators “because” and “since” are interchangeable: I could have used “because” in place of “since” or “since” in the place of “because” and the meaning of the sentences would have been the same.  In addition to premise indicators, there are also conclusion indicators.  Conclusion indicators mark that what follows is the conclusion of an argument.  For example,

In this example, the word “so” is a conclusion indicator because what follows it is a statement that someone is trying to establish as true (i.e., a conclusion).  Here is another example of a conclusion indicator:

In this example, the word “therefore” is a conclusion indicator because what follows it is a statement that someone is trying to establish as true (i.e., a conclusion).  As before, in both of these cases the conclusion indicators “so” and “therefore” are interchangeable: I could have used “so” in place of “therefore” or “therefore” in the place of “so” and the meaning of the sentences would have been the same. 

Table 1 contains a list of some common premise and conclusion indicators:

 Although these words and phrases can be used to identify the premises and conclusions of arguments, they are not failsafe methods of doing so.  Just because a sentence contains them does not mean that you are dealing with an argument.  This can easily be shown by examples like these:

Although “since” can function as a premise indicator and although “so” can function as a conclusion indicator, neither one is doing so here.  This shows that you can’t simply mindlessly use occurrences of these words in sentences to show that there is an argument being made.  Rather, we have to rely on our understanding of the English sentence in order to determine whether an argument is being made or not.  Thus, the best way to determine whether an argument is present is by asking the question: Is there a statement that someone is trying to establish as true or explain why it is true by basing it on some other statement?  If so, then there is an argument present.  If not, then there isn’t.  Notice that if we apply this method to the above examples, we will see that there is no argument present because there is no statement that someone is trying to establish as true by basing it on some other statement.  For example, the sentence “I have been running competitively since 1999” just contains one statement, not two.  But arguments always require at least two separate statements—one premise and one conclusion, so it cannot possibly be an argument. 

Another way of explaining why these occurrences of “so” and “since” do not indicate that an argument is present is by noting that both premise indicators and conclusion indicators are, grammatically, conjunctions.  A grammatical conjunction is a word that connects two separate statements.  So, if a word or term is truly being used as a premise or conclusion indicator, it must connect two separate statements.  Thus, if “since” were really functioning as a premise indicator in the above example then what followed it would be a statement.  But “1999” is not a statement at all.  Likewise, in the second example “so” is not being used as a conclusion indicator because it is not conjoining two separate statements.  Rather, it is being used to modify the extent of “happy.”  In contrast, if I were to say “Tom was sleeping, so he couldn’t have answered the phone,” then “so” is being used as a conclusion indicator.  In this case, there are clearly two separate statements (“Tom was sleeping” and “Tom couldn’t have answered the phone”) and one is being used as the basis for thinking that the other is true. 

If there is any doubt about whether a word is truly a premise/conclusion indicator or not, you can use the substitution test.  Simply substitute another word or phrase from the list of premise indicators or conclusion indicators and see if the resulting sentence still makes sense.  If it does, then you are probably dealing with an argument.  If it doesn’t, then you probably aren’t.  For example, we can substitute “it follows that” for “so” in the Bob-the-arsonist example:

However, we cannot substitute “because” for “so” in the so-happy-I-finished-that-class example:

Obviously, in the latter case the substitution of one conclusion indicator for another makes the sentence meaningless, which means that the “so” that occurred originally wasn’t functioning as a conclusion indicator.

Do Quiz 2b before moving further in the course.