IT 422: Intelligence Systems FOL Extra

At least two students love AI

Ǝ x,y ┐(x=y) Student(x) Loves(x,AI) Student(y) Loves(y,AI)

or

∃x y (Student(x) ∃ Loves(x,AI ) Student(y) ∧ Loves(y,AI) ∧ x ≠ y

• Richard has exactly two brothers, John and Geoffrey

Brother (John,Richard ) Brother ∧(Geoffrey,Richard) John ∧ ≠ Geoffrey

∧ ∀x Brother (x,Richard ) (x=John ⇒ ∨x=Geoffrey)