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 writing out the argument in symbolic form, replace the letters so that the premises are uncontroversially true. (The conclusion doesn’t have to be controversial, and the assignment is easier if it isn’t.) List the argument form in parentheses at the end of the conclusion.

Sample:

1. A → B

2. A

\ 3. B

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

2. My car ran out of gas.

3. Therefore, it must have stopped running. (Modus Ponens)

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

Grammar and Spelling: Make sure that your papers are clearly written – i.e., that the meaning is clear enough that any other student would be able to understand it. Papers will be downgraded for spelling, grammatical, and stylistic errors if there are more than 2 per page.

Sources: You shouldn’t use any outside sources since your arguments are supposed to be original.

Format: Typed, 12 point type, 1-1.5 inch margins, number and staple pages if more than one page. Make sure that the truth tables are neat and legible.

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