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Reflect and discuss a time wen you were personally guilty of committing one of the informal fallacies. (This applies to lessons 12, 13 and 14, but not 15 which is directly above.) Fallacies of Presumption, Ambiguity, and Grammatical Analogy This is basically a cluster of three smaller groups of fallacies. Fallacies of presumption occur when the premises presume what they purport to prove. Fallacies of Ambiguity occur when a passage is too ambiguous to be certain what is happening or being said. Finally, fallacies of grammatical analogy occur when we incorrectly ascribe a transference of attributes; it can be from part to whole or whole to part. Presumption Begging the Question- actually has three different types, but again like false cause, you will only need to identify it as begging the question. The first type is when key, but shaky premise is left out. Murder is morally wrong. This being the case, it follows the abortion is morally wrong. Now, you might personally agree with this passage, however, logically speaking it has left out the premise that equates abortion with murder, which is what the whole debate is about. The second type occurs when the arguer basically just reasserts the premise as the conclusion. In other words, they basically just say the same thing in a slightly different way. I call this the small circle reasoning. For example: Anyone who preaches revolution has a vision of the future for the simple reason that if a person has no vision of the future he could not possibly preach revolution. Finally, we have the big circle, or circular reasoning. This occurs when a person asserts A then B then C then D therefore A. For example: The death penalty is clearly immoral. This is so because life is intrinsically valuable. And this follows from the fact that human beings are ends in themselves. And we know this is true because human beings have a right not to be killed–which follows from the fact that the state has no right to take human life. And why is this true? Because the death penalty is clearly immoral.   Complex Question- occurs when you try to trap the person with a hidden question. For example: Have you stopped cheating on test? These are largely context driven, meaning you kind of nee

d to know the people talking to know for sure if it is a complex question. Consequently, these won’t show up on the test. False Dichotomy- occurs when the arguer falsely limits you to only two options. A dichotomy is a choice between two options, hence false dichotomy is when they say it is either A or B when in fact there are other possibilities. If you didn’t notice, this one has a buzzword. For it to be a false dichotomy there has to be a premise that says: it is either…or. Suppressed Evidence- occurs whenever the arguer leaves out vital information that you would need to know to make an intelligent assessment. For example: Hello, Mr. Mullins, I am calling to let you know that you have won a fantastic vacation is sunny Florida. The suppressed evidence being that I have to get there, and once there I have to set through a four hour high pressure time share sale pitch. Equivocation- occurs when the arguer uses one word in two different ways but isn’t’ clear about it. For example: How many mice does it take to *screw in a light bulb? Two, but don’t ask me how they got in the light bulb. Amphiboly- occurs whenever ambiguity makes it difficult to ascertain exactly what is happening. It can occur with just simple ambiguity, or when bad grammar creates an ambiguity. The bad grammar one is harder to catch because we are generally so bad at grammar that our minds automatically correct o for it. For example: Professor Johnson said that he will give a lecture about heart attacks in the biology lecture hall. Apparently, there are a lot of heart attacks in that hall. Composition- occurs when you ascribe characteristic from the part to the whole in a way that it doesn’t work. Keep in mind that it can be done correctly. For example, The Brooklyn Bridge is made out of atoms. Atoms are tiny and invisible. Therefore, the Brooklyn Bridge is tiny and invisible. Division- is the opposite of composition and occurs when you falsely ascribe attributes from the whole to the part. For example: Lake Erie contains catfish, therefore every square inch contains catfish. Again, remember, both composition and division can be done correctly.   Quick reminder: all of these are only fallacies when they are used to win an argument.