1. A -> (D -> E) 2. F -> [(A & B) v (A & ~B)] concl: (F & D) -> E 3. F -> [A & (Bv~B)] 2,DL (distributive law, "take out A & " 4. F -> A 3,CT (conjunction with a tautology Bv~B) 5. F -> (D -> E) 1,4,HS (hypothetical syllogism) 6. ~F v (D -> E) 5,CD (conditional to disjunction) 7. -F v (~D v E) 6,CD (conditional to disjunction) 8. (~F v ~D) v E 7, (associative law) 9. ~(F & D) v E 8,DM (deMorgan's law) 10. (F & D) -> F 9,CD (disjunction to conditional) I did it in 10 lines. Have you studied "conditional to disjunction" and its reverse "disjunction to conditional)? Is that what you label "CP"? [Some books label differently]. Edwin