How does Morris Zapp feel about the letter he receives from Philip Swallow while at Lake Como?

Morris Zapp receives a letter from Philip Swallow while he is at Lake Como accepting, belatedly, Zapp's invitation to the conference in Jerusalem. He tells Zapp about finding Joy Simpson, who after all is not dead. He also tells Zapp about being "madly in love," and this annoys Morris, who feels that at age 50, Philip should be beyond such effusions of sentiment. He firmly believes that love is only a cultural phenomenon and not real, and does not, of course, admit to himself that he might be jealous. He also couches his disapproval in annoyance at having been thrust into a position of lying to Hilary and mentally chastises Philip's light treatment of his marriage vows.