Example of Rule Application

• Facts
  1. (age Chris 39)
  2. (age Bob 39)
  3. (age Ian 33)
  4. (age Fred)
• Rules
  1. if (age ?X 39) => (assert (is-old ?X))
  2. if (age ?X ?Y) => (assert (has-age ?X))
• What rules get applied?
• What facts are added?
• What order are the rules applied in?