PHL111 Valid Reasoning, current assignments




Current Assignments
NOTE: please do me the favor of
  1. logging into Angel and
  2. Going to the Learning Modules
  3. Clicking on "Repository - Philosophy Department Respository"
  4. Completing the online evaluations.
They are anonymous. I'm trying to save paper for the class and so am using the online evals. However, that means I depend on you to take the time to do them. It's only two minutes! I appreciate it greatly if you can do them.


December 8
I'll have office hours from 9:00 a.m. -- 10:00 a.m., and from 1:00 p.m. to 3:30 p.m.

I was asked for some practice problems. Here are a few. I've posted some of the answers here.

Try to prove these theorems:
  1. Conclusion: ((∀x(Fx → Gx) ^ ∃x(Fx ^ Hx)) → ∃x(Gx ^ Hx))
  2. Conclusion: (∀x(Fx ↔ Gx) → (∃xFx ↔ ∃xGx))
Make an informal model to illustrate the following are invalid:
  1. Premises: ∀x(Fx → Gx), ¬Fa. Conclusion: ¬Ga.
  2. Premises: ∀x(Fx → Gx), Ga. Conclusion: Fa.
Translate the following:
  1. All and only orcs eat kobolds.
  2. All orcs are either from Mordor or Moria.
  3. Something is an orc from Moria that eats raw fish.
  4. Every orc is taller than Frodo.
  5. Frodo is taller than some kobold.
  6. No kobold is taller than Frodo, but some dwarves are taller than Frodo.
  7. Morder is a worse place to spend Spring break than Rivendell.
  8. [See if you can do this with the same predicate you used in problem 7:] Mordor is the worst place to spend Spring break.
December 10
Final exam, 8:00 a.m. -- 10:00 a.m.

Watch all five of these videos before you start studying for the final. They are short and they will do you a ton of good.




Tentative/expected Assignments (subject to revision)