Argumentation is usually associated with debate. Using argumentation in public speaking does not require being adversarial. To use it effectively can enhance the experience for the listener.

Your first thought might be to avoid it, especially when trying to persuade. The kind of argument being discussed here is not bickering or being obnoxious or even debate. Do not think of it as attacking the opposing point of view.

In its simplest form, it is putting forth reasons for or against a point of view. It can involve deductive reasoning, presentation and elaboration. It starts with a proposition, the expression of a point of view on a subject. Then supporting evidence is added and principles to support the proposition are used. Follow through with reasoning on the matter, applying inductions and deductions to the proposed thought.

An informative speech is presented as information or fact even though it is given as one person's interpretation of that information. Argumentation requires calling into question that interpretation and coming to its defense, refuting it, or offering a new view point.

Why Use Argumentation

Some subjects by their nature will have proponents on one side or the other feel there is a lack of empirical evidence. To come to a conclusion would be difficult because these issues are moral, scientific, religious, or too deep to be answered by scientific method alone. To address an audience in these instances will require using argumentation.

You need a Claim or Thesis Statement

Your speech needs to be on purpose. What do you want the audience to walk away with? What is your Most Wanted Response? Typically the narrower and more tightly focused the theme the better. So start with a focused claim or thesis statement.

For instance, to say evolution is wrong and creation is right or visa versa is so broad that it will amount to trying to lob a bag of stinky garbage into the opposing camps. However if you were to argue in a reasoning manner on a particular aspect of a belief, you might get a chance to come back for further discussion. Avoid the attack mentality.

As a general rule: Do not attack the closest and most cherished beliefs of those you want to persuade. This would be like telling your daughter not to love some guy she is already involved with. No matter how sleazy you think he is she will see him differently.

Also do not attack generalities. It would be like standing up wind and trying to bombard the opponents of your view with spray pepper in their eyes and then saying, can't you see? They will probably close their eyes before any damage can be done and they will stay closed until the danger is past or you are done talking.

However if you kindly and respectfully present why you find it hard to accept a particular proposition and provide good argumentation, you have a chance at eroding the support of the other sides view. Always respect their differing opinion.

For that matter, don't attack their opinion. It is something they possess and cherish. Rather, demonstrate why you find it difficult accept their opinion based on your evidence or logic. No emotions. Just sound reasons.

Think of your argumentation as a means of education. Rather than attacking a belief, you're offering an alternative opinion.

Next acknowledge the reasons for differing opinions. Acknowledgement of these will help lay a foundation for the argument you will be presenting.

Building an argument requires knowing five things.

1) Is the audience friendly, hostile, or neutral? You need to know the audience to know how to proceed. If they agree with you, you will be preaching to the choir. If they disagree, an entirely different tactic is required.

2) Understanding why we have different opinions.

A) The different sides of the proposition have had different life experiences.

B) They may have had the similar experiences but have drawn different conclusions from them.

C) They look to a different authority or source as a basis for forming an opinion.

Any one single difference of opinion can involve one or all three of these reasons.
So to be able to profitably and reasonably present an argument requires understanding the causes for differing opinions. This enables the speech to deal with the root cause of the disagreement.

Next set the Ground Work

3) Identify the proposition for your audience. It needs to be phrased as an issue where clear affirmative and negative sides can be taken.

4) Give definition to any terms within the proposition. This makes it possible for everyone to understand the subject under consideration. Don't argue how sweet 'Jonathan' Apples when your audience is thinking 'Granny Smith' apples. Take time to define these elements before presenting your argument.

5) Identify any issues that directly relate to the proposition and appeal to your Most Wanted Response. Focus on these to avoid rambling. Now you're ready for evidence.

Argumentation in these instances requires creating credible arguments and identifying faulty reasoning at times using informal logic. Facts alone will not always win an argument. Being understanding, reasonable, and setting a few ground rules, argumentation can enhance a speech.