The Building Blocks of Logic SYLLOGISMS IT’S A LITTLE BIT LIKE MATH… IF A=B And C=A Then B=C All humans have brains. Mrs. Miedwig is a human. Mrs. Miedwig has a brain. SOUND, VALID, OR INVALID? Sound= The premises are both unequivocally true Valid= At least one of the premises is up for debate Invalid= The two premises do not have to lead to that conclusion RELATIONSHIP TO TOULMIN Warrant: All humans have a heart. Data/ Support: Mrs. Miedwig is human. Claim: Mrs. Miedwig has a heart. Let’s talk about ORDER: Warrant: Good schools contain strong fine arts programs. Data/ Support: Crystal Lake South has a strong fine arts program. Claim: Crystal Lake South is a good school. ENTHYMEME A syllogism as stated in writing, typically with one premise missing. This usually means there’s more to say to defend your ideas. Examples: Assisted suicide is wrong because killing is wrong. If killing babies is wrong, then abortion is obviously wrong. Capital punishment is wrong because it is killing someone. ANOTHER EXAMPLE Full syllogism – All humans are mortal. (This one is left out of the enthymeme) Michael is human. Therefore, Michael is mortal. Enthymeme – Michael is mortal because he’s human. EXAMPLE IN MLK “Since I feel that you are men of genuine good will and that your criticisms are sincerely set forth, I want to try to answer your statement in what I hope will be patient and reasonable terms.” Syllogism: Sincere criticism from good people should be answered. You are good people with sincere criticism. Your criticism should be answered. ANOTHER EXAMPLE “The purpose of our direct-action program is to create a situation so crisis-packed that it will inevitably open the door to negotiation.” Syllogism: Situations that are crisis packed open the door to negotiation. The situation we are creating is crisis packed. Our situation will open the door to negotiation PRACTICAL APPLICATION Look for assumptions in your own writing and be sure to defend them. (Warrants!) Look for assumptions in other people’s writing and attack them. (Debates!) Watch out for invalid syllogisms/ invalid logic. Example: Men are stronger than women, so women cannot serve in the military. “THE CASE FOR TORTURE” Find examples where Levin uses syllogisms within his argument and write them out. Write a syllogism for Levin’s OVERALL argument. Is Levin’s argument sound? valid? invalid? Explain your answer.