Unformatted text preview: Lecture 6 Lecture 6 Finding a target Finding a target Suppose that I ask you to simplify the following expression by using the algebraic system that we have been discussing: [¬(¬A ∧¬B) ∨¬B] ∧ A Will you begin by identifying a target or will you just start applying the rules without a direction in mind? Vampires and Zombies Vampires and Zombies
You are on an island where there are two types of inhabitants: zombies (always tell the truth) and vampires (always lie). You meet Albert and Betty on the island. Albert says : At least one of us is a vampire. What do you know about these two? More Vampires and Zombies More Vampires and Zombies
You meet Albert, Betty and Carl on the island. Albert says: None of us is a zombie. Betty say: I am the only vampire. What do you know about these three? SL in Natural Language SL in Natural Language
Truthvalue test: A sentence can be construed as a truthfunctional compound, formed by applying sentential connectives, only if its truthvalue is always determined according to the truthtable of that connective. (p.83) Applying the TruthValue Test Applying the TruthValue Test “John was unharmed by the accident.” (p.83) “John is unhappy today.” (p.84) HW 3.3 HW 3.3
A: Ann is married B: Barbara is married C: Clair is married D: Dorothy is married At least one of the four women is married. If one of the four women is married, all of them are. Ann and Clair have the same marital status. HW 3.5 HW 3.5 No one can be good for long if goodness is not in demand. If there are obstacles, then the shortest line between two points may be a crooked line. Literary works cannot be taken over like factories, or literary forms of expression like industrial methods. The Island of Questioners The Island of Questioners There are two types of inhabitants, A and B. Type A ask only yes/no questions whose correct answer is yes. Type B ask only yes/no questions whose correct answer is no. A person on the island asks you “Am I of type B?” What can you conclude? If you like the kind of puzzles that If you like the kind of puzzles that we discussed today, then …
Have a look at the following books by the great Ray Smullyan: What is the name of this book? The Lady or the Tiger? and Other Logic Puzzles ...
View
Full Document
 Spring '11
 H
 Truthvalue test, island. Albert, Zombies Vampires, TruthValue Test Applying, Zombies More Vampires

Click to edit the document details