Question

How is the counterexample method applied to deductive arguments?

What is the point of deconstructing arguments using diagramming?

How can you test moral premises?

When is the use of a slippery slope argument legitimate? When does it constitute a fallacy?

Answer 1

An argument is invalid if the conclusion doesn't follow necessarily from the premises. In deductive arguments, the counterexample method is used to expose what is wrong with an argument that is invalid. There are essentially two steps involved in applying the counterexample method:

1. Isolate the argument form;
2. Construct an argument with the same form that is obviously invalid. This is the counterexample.

Let us take the following example of an invalid argument: "Some people are Muslims. Some people are terrorists. Therefore some Muslims are terrorists."

Step 1. Isolate the argument form: If we do this we get: "Some P are T. Some P are M. Therefore some M are T,"

Step 2. Construct the counterexample: "Some plants are green. Some plants are yellow, Therefore some green plants are yellow."

From this, we can clearly deduce that the argument presented is invalid,

Please post the other questions separately as we are supposed to answer just one question or four sub parts of a single question.