Introduction for Class: Symbolizations in PL


Universe of Discourse: Cats (and only cats! for this symbolization felines are our only subject)

Mx: x is a mammal, Rx: x is a reptile; Wx: x is wild.

f: Felix the Cat (pretend he's a real cat)
t: Tony the Tiger (of course, he's real, he's on TV)

Keep in mind that the subject under discussion, the "universe of discourse" is just cats. We are not concerned here with anything but cats. Forget about dogs and mice, etc.! This is very restrictive. We'll begin to remove this restriction in 6.2.

Don't forget how to get an answer. Also, there are good keyboard shortcuts: Instead of typing out '(^x)' for the universal quantifier, type 'Vx' (no parentheses needed). This will turn into '(^x)' after you press TAB. Similarly, for the existential quantifier, type '3x'.
  1. Felix is a mammal.
  2. If Felix is a mammal, then so is Tony.
  3. Some (cats) are wild.
  4. Some (cats) are wild but not Tony.
  5. All (cats) are mammals.