Guidelines for Propositional Argument Portfolio

In this assignment, you will create 3 original examples of sound Propositional Arguments, to show that you know how to use them correctly.

1. Select three different valid Propositional Argument forms. (See below for examples.) Make sure that the assignment includes at least one negation, one conjunction, one disjunction, and one conditional statement.

2. After listing the name of the argument form and writing out the argument in symbolic form, replace the letters with statements and make sure that the premises are uncontroversially true. (The conclusion doesn’t have to be controversial, and the assignment is easier if it isn’t.)

Sample:

Modus Ponens

1. A → B 1. If my car runs out of gas, then it will stop running.

2. A 2. My car ran out of gas.

\ 3. B 3. Therefore, it must have stopped running.

3. Use a Truth Table to demonstrate that each of the arguments are valid.

4. When you have completed a draft of your portfolio, double check your grammar and spelling, the formatting of the paper, and each item on the checklist below. Then write or type the following signing statement and sign your name: “I have carefully read and followed the guidelines and thoroughly edited my paper for grammar, spelling, and formatting.”

Format: Typed, 12 point type, 1-1.5 inch margins, number and staple pages if more than one page. Include a title and make sure that the parts of the portfolio are neatly arranged.

Checklist

A. Originality – None of the arguments should use statements that were used in class or in our textbook, and none of these statements should be used more than once in your portfolio.

B. Identical Meaning – In each argument, the statements represented by the same letters must be identical in meaning.

C. Number both Premises and the Conclusion – Each premise and conclusion in an argument should be numbered and on a separate line, and the conclusion should start with ‘Therefore …’

D. Validity – All three of the Propositional Arguments must be Valid.

E. Uncontroversially True Premises – Make sure that each of the premises is uncontroversially true.

F. Diversity – Each argument form must be different, and you must include at least one negation, one conjunction, one disjunction, and one conditional statement in the assignment (See #1 above.)

G. Legible Diagrams – Make sure the Truth Tables are neat and are large enough to be easily read.

Examples of Valid Propositional Arguments:

Modus Ponens

1. A → B

2. A

\ 3. B

Modus Tollens

1. A → B

2. ~ B

\ 3. ~ A

Disjunctive Syllogism

1. A v B

2. ~ A

\ 3. B

or

1. A v B

2. ~ B

\ 3. A

Hypothetical Syllogism

1. A → B

2. B → C

\ 3. A → C

Conjunction

1. A

2. B

\ 3. A & B

Simplification

1. A & B

\ 2. A

or

1. A & B

\ 2. B