Confusion with Setup

Hello! For the contrapositive chain, we began with rule #6: "No H or No L -> No P" etc. For rule 5's contra chain, we didn't do "No P or No T -> No F"; we excluded P and stated "No T -> No F -> No G." I'm wondering why this is because it is important to me to understand why P would not be included in the list of entities (H, L, and T) necessary for the diagram. Please help! @Mehran