Reading for Monday, September 21:

• Grimaldi:  2.1
• Pay particular attention to Example 2.2.  Express p ->q as an English sentence.  Use this expression to explain why p->q is true when p is false and q is true (row 2 of Table 2.2)
• How many rows are there in a truth table for a compound statement  made up of two primitive statements?  What if there are n primitive statements?
• What kind of statment is p /\ ~p?  p\/~p ?

• Grimaldi:  2.2
• Focus on showing logical equivalence using "Laws of Logic".  Duality and Substitution Rules are less important.
• What logical equivalences allow us to eliminate the connectives -> and <=> from compound statements?
• Negation of an implication:  express in English without beginning with the word "not".  (Ex. 2.13)
• What are the contrapositive, inverse and converse of the implication p->q?  Which are logically equivalent to p->q?

• Grimaldi:  2.3  (Things to think about when you are reading the section)
• This section is a little overwhelming.  Focus on understanding how to demonstrate the validity of an argument.  Try not to get bogged down by all of the names of the rules.
• What does it mean to say that "p logically implies q"?
• How would you show that a rule of inference (say Syllogism) is valid using a truth table?
• Try 2.3 #5
• Why are the arguments given on p85 invalid?

• Grimaldi: