Hypothetical Syllogisms- Conditional Arguments

Hypothetical syllogisms (conditional arguments) can have two valid and two invalid structures. The two valid structures are affirming the antecedent (modus ponens) and denying the consequent (modus tollens). The two invalid structures, or fallacies, are denying the antecedent and affirming the consequent. Determine if the arguments below are valid or invalid and what form they take. The first one has been done for you.
(NOTE: The term "modus pollens" has been used in some texts as a version of "modus ponens." For the purposes of this exercise, "modus ponens" will be used.)SAMPLE: Chris and Nick would be very happy if the Browns beat the Steelers. The Browns did beat the Steelers, so Chris and Nick are very happy, indeed.Valid Modus Ponens (Affirming the Antecedent)1. Madeline must have known the material for the test, because if a person knows the material, that person will always get an A, and Madeline was one of the students that got an A.2. Anastasia believes that if she treats people honestly and with an open mind, she will have diverse friendships. She is honest and open-minded and has friends all over the world.3. Roberto thought that if he worked very hard, his boss would give him a raise or a promotion. He made sure she noticed him, but she did not give him a raise or promotion. He thought he must not have worked hard enough.4. "I'm still eating too much ice cream," lamented George. "My waist measurement is the same as it was six months ago. I know if I didn't eat so much ice cream, I would reduce my waist size."5. The good way to make sure we pay fewer taxes is to elect conservatives. We must not have elected enough conservatives, because we are paying more taxes.6. If my neighbor were a decent human being, he wouldn't let his tree leaves fall onto my property. But he's not a decent human being, so we get to clean his tree leaves as well as ours.7. If I could only understand the concept of hypothetical syllogisms, I would get an A in class. Hurray! I got an A in class, so I must have understood the concept of hypothetical syllogisms.More information on this topic can be found here. This message has been edited by AdminPhat, 04-29-2005 02:38 AM

Hello, HT! Welcome to EvC! After reading your post, I said to myself, "This person wants to be a teacher!" Logic can be a good thing. My only concern is that the opening is a bit long. Lets cut it down to perhaps ten syllogistic examples between both of your proposed new topics. I would like you to combine both of your Proposed New Topics into one, as they are similar. Do you see the edit button? You can use it to reword your opening post.Perhaps you could give us a brief introduction of yourself and why you feel led to teach us this logic that you are learning. Some of the other moderators may also have some input and suggestions for you. Keep up the learning! You will be an asset to society and to your family!This message has been edited by AdminPhat, 04-29-2005 02:30 AM

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Yes Iam a teacher.I just want to see some response to the questions that i posted.{Note: Message 1 was spun off as the new topic on 4/29/05, but the topic wasn't then closed. Closing now (5/5/05). - Adminnemooseus}This message has been edited by Adminnemooseus, 05-05-2005 11:51 PM