Critical Thinking: Extended Arguments and Inference Indicators

Introduction
Up until now we've been applying our analytical skills to relatively simple arguments.  Now we will begin to apply those skills to extended arguments.  What's an extended argument?  Well, I'm glad you asked:  An extended argument is one that has a main conclusion supported by premises which themselves are in turn supported by sub-premises.  

When a major premise is supported by sub-premises we can consider the major premise to be sub-conclusion.  Extended arguments are often more difficult to break down into premises and conclusion because there's a lot more information involved.  Also, sometimes it can be difficult to disentangle the sub-premises from the premises and the final conclusion from the sub-conclusion(s).  

Some General Strategies As a general heuristic, work backwards from conclusion to premises to sub-premises.  First, try to identify the main conclusion.  A good way to go about it is to ask yourself, "what is the argument trying to convince me of?"  If all else fails, look at the title of the article...

Once you answer that question ask yourself "why does the arguer think I should believe this?" This will help you identify the main premises. What's left will often be sub-premises. 

In some extended arguments, once we've identified the main components it can still be difficult to distinguish what is supporting what--especially between a sub-conclusion and the main conclusion.  Here's a little trick to help make the distinction.  

Suppose you have 2 statements and you're not sure which is the main conclusion and which is a sub-conclusion.  Read one statement followed by "therefore" then read the next.  If it sounds awkward, try it the other way around.  Often, this can help sort things out.  

Extended Arguments:  Argument Extend-a-Mix
So, why should we care about extended arguments?  There are a couple of reasons.  First, most arguments we encounter "in the wild" as articles, essays, and books come to us as extended arguments.  Second, as you may have noticed, the premises of simple arguments don't always withstand scrutiny.  

This implies that if an arguer wishes to maintain her position against criticism, she will have to provide further sub-premises (i.e., reasons and evidence) to support the premises which are being criticized.  A good arguer will anticipate criticism and so will include the sub-premises as a pre-emptive defensive strike.  

Lets look at an example to illustrate what I'm talking about: 

Sample Simple Argument:
P1  Mugatu invented the pianokey necktie.
P2  The pianokey necktie was an important milestone in men's fashion.
C    Therefore, Mugatu is a fashion genius. 

Suppose someone takes issue with the premise acceptability of P2.  (Of course, they'd be wrong, but just suppose....) The person making this argument would then have to give further premises (reasons or evidence) to support P2.  For example, they might say "all the cool kids owned one."  The fact that all the cool kids owned a pianokey necktie further supports the premise that the pianokey necktie was an important milestone in men's fashion. 

The extended version of the argument would look like this:
P1  Mugatu invented the pianokey necktie.
P2  All the cool kids owned pianokey neckties.
P3  Given that P2, the pianokey necktie was an important milestone in men's fashion.
C   Therefore, Mugatu is a fashion genius.

Analyzing Extended Arguments Using Inference Indicators
As I mentioned earlier, a problem with analyzing extended arguments is trying to distinguish between premises, sub-premises, and conclusion.  But do not dispair fair child.  There are yet more tricks to help us.  

Paying attention to inference indicators will often help us to disentangle argument components.  An inference indicator is a word that gives us a sign as to whether the sentence is a premise or a conclusion.

Here are some common indicators for premises:  Since, because, for, as can be deduced from, given that, and the reasons are.

Here are some common indicators for conclusions:  Consequentially, so it follows, thus, hence, therefore, and we conclude that.

Now go forth and analyze.