Syllogism A chain of reasoning moving from general

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Syllogism • A chain of reasoning moving from general, universal principles to specific instances.

Syllogism • A chain of reasoning moving from general, universal principles to specific instances. • A form of deductive reasoning consisting of a major premise, a minor premise, and a conclusion. • Premise – a proposition supporting or helping to support a conclusion.

PICTURE OF A SYLLOGISM Suppose we know that all the things matching category “B”

PICTURE OF A SYLLOGISM Suppose we know that all the things matching category “B” fits completely inside the larger category “A. ” That’s the major premise, or the first argument. Suppose we can also prove that all things matching category “C” also fit inside the category “B. ” That’s the minor premise, or the second argument. From these two statements, we can also conclude that all of “C” must fit in category “A” as well.

Structure of an Argument Major Premise: All zebras are striped animals. Minor Premise: No

Structure of an Argument Major Premise: All zebras are striped animals. Minor Premise: No zebras are polar bears. Conclusion: Therefore, no polar bears are striped animals.

Validity Testing Major Premise: All clowns are funny individuals. Minor Premise: Some sad people

Validity Testing Major Premise: All clowns are funny individuals. Minor Premise: Some sad people are clowns. Conclusion: Therefore, some sad people are funny individuals.

Validity Testing Major Premise: Some sticky substances are yucky things. Minor Premise: All taffy

Validity Testing Major Premise: Some sticky substances are yucky things. Minor Premise: All taffy is a sticky substance. Conclusion: Therefore, some taffy is a yucky thing.

Validity Testing Major Premise: All flies are winged creatures. Minor Premise: All butterflies are

Validity Testing Major Premise: All flies are winged creatures. Minor Premise: All butterflies are winged creatures. Conclusion: Therefore, all butterflies are flies.

Validity Testing Major Premise: Those who study rhetoric speak eloquently. Minor Premise: AP Language

Validity Testing Major Premise: Those who study rhetoric speak eloquently. Minor Premise: AP Language and Composition students study rhetoric. Conclusion: AP Language and Composition students speak eloquently.

ENTHYMEME (EN – thuh- meme) • A shortened syllogism that serves the purpose of

ENTHYMEME (EN – thuh- meme) • A shortened syllogism that serves the purpose of a more practical and expedient way to argue • An incomplete syllogism, in which one or more premises are unexpressed

ENTHYMEME (EN – thuh- meme) • Consider the following syllogism: • Major Premise: All

ENTHYMEME (EN – thuh- meme) • Consider the following syllogism: • Major Premise: All people are mortal. • Minor Premise: Aristotle was a person. • Conclusion: Therefore, Aristotle was a mortal. Restructured as an enthymeme: Aristotle was mortal because he was a person.

ENTHYMEME (EN – thuh- meme) Aristotle states that under LOGOS, or the content of

ENTHYMEME (EN – thuh- meme) Aristotle states that under LOGOS, or the content of the message, the two most powerful tools are the enthymeme and the example. In an argument, the speaker or writer can leave out the universal principle typically stated in a syllogism because everyone should agree with it. For example, everyone should agree that all people are mortal.

ENTHYMEME (EN – thuh- meme) “It is quite recent history, Lord Randolph was Chancellor

ENTHYMEME (EN – thuh- meme) “It is quite recent history, Lord Randolph was Chancellor of the Exchequer, Lord Salisbury was Prime Minister, as he is now. And on the same issue of economy Lord Randolph Churchill went down - - forever. But wise words, Sir, stand the test of time. And his words were wise. ” - from the movie Young Winston

ENTHYMEME (EN – thuh- meme) MAJOR PREMISE: MINOR PREMISE: CONCLUSION: Which is not stated?

ENTHYMEME (EN – thuh- meme) MAJOR PREMISE: MINOR PREMISE: CONCLUSION: Which is not stated?

ENTHYMEME (EN – thuh- meme) I wanted to serve as President because I love

ENTHYMEME (EN – thuh- meme) I wanted to serve as President because I love this country and because I love the people of this Nation. ” -Jimmy Carter, 1980 Concession Address Major Premise: Minor Premise: Conclusion:

ENTHYMEME (EN – thuh- meme) Dr. Eldon Tyrell: “You were made as well as

ENTHYMEME (EN – thuh- meme) Dr. Eldon Tyrell: “You were made as well as we could make you. ” Roy Batty: “But not to last. ” Dr. Eldon Tyrell: “The light that burns twice as bright burns half as long, and you have burned so very, very brightly, Roy. ”

ENTHYMEME (EN – thuh- meme) Major Premise: Minor Premise: Conclusion: Which premise was not

ENTHYMEME (EN – thuh- meme) Major Premise: Minor Premise: Conclusion: Which premise was not stated?

ENTHYMEME (EN – thuh- meme) “Ladies and gentlemen, I will not divide the Democratic

ENTHYMEME (EN – thuh- meme) “Ladies and gentlemen, I will not divide the Democratic Party. Therefore, tomorrow morning I will write to the Chairman of the Democratic Party withdrawing my candidacy. ” -Thomas F. Eagleton

ENTHYMEME (EN – thuh- meme) Major Premise: Minor Premise: Conclusion: What premise is missing?

ENTHYMEME (EN – thuh- meme) Major Premise: Minor Premise: Conclusion: What premise is missing?

ENTHYMEME (EN – thuh- meme) “Now, I don’t know or have never met my

ENTHYMEME (EN – thuh- meme) “Now, I don’t know or have never met my candidate; and for that reason I am more apt to say something good of him than anyone else. ” -Will Rogers Major Premise: Minor Premise: Conclusion:

ENTHYMEME (EN – thuh- meme) “The gloves didn’t fit. If it doesn’t fit, you

ENTHYMEME (EN – thuh- meme) “The gloves didn’t fit. If it doesn’t fit, you must acquit. ” -John Cochran, Closing arguments of the O. J. Simpson trial Major Premise: Minor Premise: Conclusion: