An argument is a set of two or more propositions related to each other in such a way that all but one of them (the premises) are supposed to provide support for the remaining one (the conclusion). When writing in long form, the structure may get lost. It is best to outline each element of the argument before hand.
Here are a few definition of elements within an argument:
- premise
- a statement whos truth is used to infer that of others. Think of this as a building block for an argument, or a link in a chain with the last link being your conclusion
- conclusion
- a proposition whose truth has been inferred on the basis of other propositions assembled with it in a logical argument
- logic
- the study of the distinction between correct and incorrect reasoning. This will provide connection between premises.
- proposition
- a statement that is declared by a declarative statement that can either be true or false. Also commonly referred to as a claim. The claim is supported by the conclusion.
- inference
- the relationship that holds between the premises and the conclusion of a logical argument, or the process of drawing a conclusion from premises that support it deductively or inductively
There are two main types of argument: deductive, and inductive.
Deductive Reasoning
A deductive argument is one in which it is impossible for the premises to be true but the conclusion false. In deductive reasoning, the conclusion follows necessarily from the premises and inferences. The premises prove of the truth of the claim (conclusion) as the truth of the premises is supposed to guarantee the truth of the conclusion.
- Premise: All dogs go to heaven when they die.
- Premise: Fido is a dog.
- Conclusion: Fido will go to heaven when he dies.
A deductive argument is valid or else invalid. An argument in which the premises do succeed in guaranteeing the conclusion is called a (deductively) valid argument. If a valid argument has true premises, then the argument is said also to be sound.
Inductive Reasoning
An inductive argument is one in which the premises are supposed to support the conclusion in such a way that if the premises are true, it is improbable that the conclusion would be false. The truth of the premises merely makes it probable that the conclusion is true.
- Premise: My last two dogs have gone to heaven when they died.
- Premise: Fido is a dog.
- Conclusion: Fido will go to heaven when he dies.
An inductive argument is an argument that is intended by the arguer to increase the likelihood of its conclusion, yet not to guarantee the conclusion. In an inductive argument, the premises are intended only to be so strong that, if they were true, then it would be unlikely that the conclusion is false.