Question: let px qx rx sx y be the predicates x...
Let P(x), Q(x), R(x), S(x, y) be the predicates, “x is a true dungeon master”, “x has sex appeal”, “x is a wood-elf”, “x is a friend to y”.
Translate the following statements into predicate logic.
• A true dungeon master is a friend to all wood-elves
• Only true dungeon masters have sex appeal
• Bob is not a friend to some wood-elf
Using the statements, prove that Bob does not have sex-appeal. Justify every line of your proof with a rule of logic as in the proofs in the text.