Topic 2: Premise Indicators

PHI332 : The Class : Argument ID : Premise Indicators

Topic 2: Premise Indicators

The technique of argument diagramming will help you learn to identify, evaluate, and construct arguments. When you diagram an argument, you will only be interested in declarative statements, and only in declarative statements that are either premises or conclusions. Whenever an author states a reason, the reason is a premise, and what the reason is for is the conclusion. It can be hard to determine when a passage contains premises and conclusions.

There are artificial languages (the study of formal logic) in which the rules of the language make it obvious when you have a premise or conclusion. But English, and all natural languages, are not so obvious. Fortunately, there are some pretty clear indicators you can trust: premise indicators and conclusion indicators. A premise indicator is a synonym for "because."

Premise indicators
because
for
since
as
firstly, . . ., secondly, . . .
(and many other possibilities)
Here are some examples:

Abortion is wrong because life is present from the moment of conception.
Since life is present from the moment of conception, abortion is wrong.
Abortion is wrong, for life is present from the moment of conception.

In example 1, the "because" clause is a premise, the other clause is the conclusion. This tells us that example 1 is an argument with one premise ("life is present from the moment of conception") and one conclusion ("abortion is wrong"). You are ready for your first diagram!

Diagram of example 1: .
Key:
a = Life is present from the moment of conception.
b = Abortion is wrong.

Every diagram will show how premises and conclusions fit together by using an arrow and putting the conclusion at the sharp end of the arrow and a premise at the blunt end of the arrow. The following diagrams are also correct for example 1, using the same key.

The important thing in all these is that the conclusion is at the sharp end, the premise at the blunt end of the arrow. The following diagrams (with the same key) are all INCORRECT:

These incorrect diagrams all mistake the premise for the conclusion and the conclusion for the premise. (To draw vertical arrows, go to your View menu, find Toolbars, and activate your Drawing toolbar, which will appear on your screen. Click on the arrow-not the "draw shapes" arrow but the "arrow" arrow! on that toolbar. Your cursor will turn into a plus sign. Hold down or "drag" the plus sign from where you want the blunt end of your arrow to be and move the plus sign to where you want the sharp end to be before releasing the hold down or "dropping.")

To complete this topic successfully, do as many of the following exercises as you find necessary to acquire the relevant skill. You have acquired the relevant skill when your answers to exercises are reliably either the same as the given answers or are alternative answers you can explain and defend:

ASSIGNMENT 1: Exercise 2.2.1

ASSIGNMENT 2: Exercise 2.2.2

ASSIGNMENT 3: Exercise 2.2.3

ASSIGNMENT 4: Exercise 2.2.4

Once you have completed this module you should:

Go on to Topic 3: Conclustion Indicators
or
Go back to Argurment ID

E-mail George Rudebusch at George.Rudebusch@nau.edu
or call (520) 523-7091