 Review: an argument can have an unstated premise. ◦ For example, “No motorcycles are allowed in the park because the regulations state that motor vehicles are not allowed entrance. ◦ No motor vehicles are allowed in the park. ◦ All motor cycles are motor vehicles. (We have to assume this premise) ◦ Therefore no motor cycles are allowed in the park.

 Review: an argument can have an unstated conclusion.  It is wrong to have hurt someone’s feelings, and that is exactly what you are doing when you speak to me like that.  Why is this a deductive argument instead of an inductive argument?  What do we mean when we say something like, “Murder is wrong.?” Do we generally mean that murder is sometimes wrong? Or do we mean that it is sometimes wrong for me, but it might be right for you? We have to put things in context and think what the person saying it really means.  All times that you hurt someone’s feelings are times you have done something wrong.  This is a time when you hurt someone’s feelings.  Therefore, this is a time that you have done something wrong.

 1. I have never taken a philosophy class that was not fun. I bet all philosophy classes are fun. ◦ Inductive  2.Since some apples are red, and all apples are fruit, some fruit is red.  Deductive  3. All mammals are warm blooded creatures, and all whales are mammals. Therefore, all whales are warm blooded creatures.  Deductive  4. Fulcher lives in Alaska. Therefore, he uses mosquito repellent.  Inductive

 I will hand you each a piece of paper. They will have either the word ‘inductive’ or ‘deductive’ on them. Depending on which paper you get, you will come up with an appropriate argument. The rest of the class will try to guess which type of argument it is. I want you to turn them in at the end of class because I might use one or two of them for an extra credit question on the test.

 If you log in to then you can take a practice quiz. In the meantime, lets go over some problems.  Do all arguments have a conclusion? ◦ Yes, but it may not be explicitly stated. ◦ Are all valid arguments sound arguments? ◦ What is the difference between a valid argument and a salad argument?  No. Can you think of an example?  If the moon were made of green cheese, then the cow will jump over the moon.  The moon is made of green cheese.  Therefore, the cow will jump over the moon.

 Do explanations and arguments serve the same purpose? ◦ No ◦ Why not? What purposes do each of them serve? ◦ Basically, an argument attempts to support or prove a conclusion, while an explanation specifies what caused something or how it works or what it is made of and so forth. Arguing that the computer is working much more slowly than it used to is not the same as explaining what caused the computer to start working much more slowly.