What is an argument? An argument is, to quote the Monty Python sketch, "a connected series of statements to establish a definite proposition." Huh? Three stages to an argument: Premises Inference Conclusion

Stage one: Premises One propositions will be/are necessary for the argument to continue. Must be stated explicitly. Called the premises of the argument. The evidence (or reasons) for accepting the argument and its conclusions.

Stage one: Premises Premises (or assertions) often indicated by phrases such as "because“ "since“ "obviously" The phrase "obviously" often viewed with suspicion, as it can be used to intimidate others into accepting dubious premises. If something doesn't seem obvious to you, don't be afraid to question it. You can always say: "Oh, yes, you're right, it is obvious" when you've heard the explanation.

Stage two: Inference Premises of argument used to obtain further propositions--process is known as inference. In inference, start with one or more propositions which have been accepted. Then derive a new proposition. Various forms of valid inference. Propositions arrived at by inference may then be used in further inference. Inference is often denoted by phrases such as "implies that" or "therefore“ etc.

Stage three: Conclusion Conclusion often stated as final stage of inference. Affirmed on the basis the original premises, and the inference from them. Conclusions are often indicated by phrases such as "therefore" "it follows that" "we conclude" etc.

Types of Argument Deductive and Inductive. NOTE: Arguments can also have unstated premises; arguments with unstated premises are called enthymemes

1. Arguments cannot be true or false. The terms “true” and “false” are properly applied only to statements. The evaluative terms that are properly applied to arguments are those defined above under the heading “Definitions of Evaluative Terms.” 2. Statements cannot be valid or invalid in the sense these terms have in logic. Statements can be true or false, but only arguments can be valid or invalid in the sense defined here.

A Deductive argument: the premises provide a guarantee of the truth of the conclusion. In a deductive argument… the premises are intended to provide support for the conclusion that is so strong that, if the premises are true, it would be impossible for the conclusion to be false.

A Deductive argument: The members of the Williams family are Susan, Nathan and Alexander. Susan wears glasses. Nathan wears glasses. Alexander wears glasses. Therefore, all members of the Williams family wear glasses.

Here is an example of a deductive argument: Every event has a cause (premise) The universe has a beginning (premise) All beginnings involve an event (premise) This implies that the beginning of the universe involved an event (inference) Therefore the universe has a cause (inference and conclusion) Note that the conclusion of one argument might be a premise in another argument. A proposition can only be called a premise or a conclusion with respect to a particular argument; the terms do not make sense in isolation.

An Inductive argument: the premises provide reasons supporting the probable truth of the conclusion. In an inductive argument, the premises are intended only to be so strong that, if they are true, then it is unlikely that the conclusion is false.

An Inductive argument: It has snowed in Massachusetts every December in recorded history. Therefore, it will snow in Massachusetts this coming December.

Contrary to what you may have been told in your English composition class, giving examples is usually a very different thing from presenting an argument. Typically, people give examples for the purpose of illustrating the meaning of the claims they make… ~not for the purpose of establishing the truth or the plausibility of those claims.

Let’s take a look at some other examples: I’ve just tested positive for HIV. Unless I receive effective treatment, I’m going to die of AIDS. Argument or Enthymeme? Everyone who tests positive for HIV dies of AIDS unless he or she receives effective treatment. I’ve just tested positive for HIV. Therefore, unless I receive effective treatment, I’m going to die of AIDS Valid or Not Valid?

The vast majority of people who test positive for HIV die of AIDS unless they receive effective treatment. I’ve just tested positive for HIV. Therefore, unless I receive effective treatment, I’m going to die of AIDS. Deductive or Inductive?