- Conditionals and biconditionals (2 points)
Read FOL, pages 91-103 (Sections 4.1-4.4). Do the following problems:
- Page 95, Problem 4.
Hand in your answers on
a disk (in PC/IBM format. Name your file 4-4.sen (as it is specified
in the problem).
- Page 104, Problem 21.
An example for a similar proof is given on page 102 of FOL. Make sure
to understand this example before attempting to solve this problem.
- More reading
Read FOL, page 112 (Section 4.7).
- Validity (3 points)
Give a semantic and a syntactic proof
for each of the following valid steps
- Modus tollens: From "A implies B" and "not B" infer "not A".
- Strenghening the antecedent: From "B implies C" infer "(A and B)
- Weakening the consequent: From "A implies B" infer "A implies (B
- First order logic (Here it comes!) (3points)
Read carefully FOL, pages 115-127 (Sections 5.1-5.8).
Do the following problems:
- Page 119, Problem 1 (Filename: 5-1.sen).
- Page 124, Problem 6 (Filename: 5-6.wld).
- Page 125, Problem 10.
- Page 127, Problem 11 (Filename: 5-11.sen).
- Page 131, Problem 17.
- Even more readings and questions (2 points)
Read FOL, pages 132-141 (Sections 5.9-5.10), and pages 152 (Section
- Write up three questions from the readings assigned in this
homework: either questions about something that you did
not understand at all, or questions about what you think
is most important. If you choose the latter, give also