Working with Arguments
First, you need to know what deductive reasoning is. To help define it, the counterpart of deductive reasoning, which is inductive reasoning, will be introduced first.

Inductive Reasoning
Inductive reasoning consists of making observations and then drawing conclusions based on those observations.
Like a detective, you use inductive reasoning all the time in your life. You might notice, for example, that every time you eat a hot dog with chili and onions, you get a stomachache. Using inductive reasoning, you could logically conclude that the chili dogs cause indigestion, and that you should probably stop eating them. Similarly, you might notice that your cat tries ti scratch you every time you rub her stomach. You could logically conclude that she does not like her stomach rubbed. In both examples, what you are doing is moving from the specific-a particular observation-to the general-a larger conclusion. Inductive reasoning starts from observation and evidence and leads to a conclusion.

Using inductive reasoning generally involves the following questions:
1. What have you observed? What evidence is available?
2. What can you conclude from that evidence?
3. Is that evidence logical?

Deductive Reasoning
Unlike inductive reasoning, which moves from specific evidence to a general conclusion, deductive reasoning does the opposite; it generally moves from a conclusion to the evidence for that conclusion. In inductive reasoning, the conclusion has to be 'figured out' and we must determine whether or not the conclusion is valid. In deductive reasoning, on the other hand, we start with the conclusion and then see if the evidence is valid, the conclusion it supports is valid as well. In other words, deductive reasoning involves asking:

1. What is the conclusion?
2. What evidence supports it?
3. Is that evidence logical?

If you can answer yes to question 3, then the conclusion should be logical and the argument sound.