Predicate Logic Example
• John likes all kinds of food.
• Apples are food.
• Chicken is food.
• Anything anyone eats and isn’t killed by is food.
• Bill eats peanuts, and is still alive.
• Sue eats everything that Bill eats.
Logical form
• John likes all kinds of food == ∀x food (x) ⇒ eats(John, x)
• Apples are food == food(apples)
• Chicken is food == food(chicken)
• Anything anyone eats and isn’t killed by is food == ∀x,y
eats(x,y) ∧ ¬killed(x) ⇒ food(y)
• Bill eats peanuts, and is still alive == eats(Bill,Peanuts) ∧
¬killed(Bill)(here we assume alive means not killed)
• Sue eats everything that Bill eats == ∀x eats (Bill,x) ⇒
eats(Sue,x)
CNF Form
predicate logic example

predicate logic example

  • 1.
    Predicate Logic Example •John likes all kinds of food. • Apples are food. • Chicken is food. • Anything anyone eats and isn’t killed by is food. • Bill eats peanuts, and is still alive. • Sue eats everything that Bill eats.
  • 2.
    Logical form • Johnlikes all kinds of food == ∀x food (x) ⇒ eats(John, x) • Apples are food == food(apples) • Chicken is food == food(chicken) • Anything anyone eats and isn’t killed by is food == ∀x,y eats(x,y) ∧ ¬killed(x) ⇒ food(y) • Bill eats peanuts, and is still alive == eats(Bill,Peanuts) ∧ ¬killed(Bill)(here we assume alive means not killed) • Sue eats everything that Bill eats == ∀x eats (Bill,x) ⇒ eats(Sue,x)
  • 3.