Deductive Arguments

Prior to beginning work on this discussion,

Read the assigned sections in Chapter 3 in your course textbook:

3.1: Basic Concepts in Deductive Reasoning

3.2: Evaluating Deductive Arguments

3.3: Types of Deductive Arguments

Chapter 3 Summary and Resources

Watch the following videos:

What Is a Deductive Argument? (Links to an external site.)

What is a Valid Argument? (Links to an external site.)

How to Make a Sound Deductive Argument (Links to an external site.)

Your instructor will choose the discussion question and post it as the first post in the discussion forum. In your discussion post, address all the elements in the prompt as thoroughly as you can.

Instructors Post:

In preparation for the Creating a Valid Argument Workshop assignment due at the end of this week, you get to practice creating a valid (and preferably sound) argument on your chosen topic (the topic you chose in Week 1). Remember that a valid argument is one that is constructed in such a way that its premises, if true, would guarantee the truth of the conclusion. A sound argument is one that is valid and has all true premises. It is a challenging thing to make a valid (and sound) argument, so this discussion is designed as practice towards that goal.

You are going to present a deductive argument on your topic (either side). Make sure that it has a valid logical form and strive to make the premises true as well (the primary purpose here is validity but try to make the premises as plausible as you can).

In their comments, your peers are going to see if they can find a way in which all of your premises could all be true and the conclusion false. If this is possible, then your argument is not quite valid yet. Do not despair, you will get to reply to them with a strengthened version of the argument, in which the goal is to eventually arrive at a version that is valid (while keeping premises that are plausibly true).

After testing for its validity, your peers will get a chance to investigate the truth of the premises (focusing mostly on the new ones added to make the argument valid). Perhaps there is a counter-example to one of your premises. If a peer presents such a response, would you agree with the objection? If so, how would you revise the premise to make it true? Would the new version of the argument be sound? If not, how would you respond to the objection?