Homework for Philosophy 270, Fall 2012
Homework on §7.7—assigned Mon 11/12 and due Wed 11/14
(to PDF format)
use a derivation to check the following and present a counterexample by using a diagram to present a counterexample that lurks in an open gap:
∀x (Rax → Fx), Rab, ¬ Fa / ∀x (Rxa → ¬ Fx)
analyze and restate using unrestricted quantifiers:
Nothing that anyone knew of explained every observation
synthesize an English sentence that has the following analysis:
(∀x: ¬ Ux) (∀y: Py) ¬ Nyx
(P: [ _ is a person]; N: [ _ noticed _ ]; U: [ _ was usual])