Who is the one person that Nero Wolfe cannot intimidate in the novel, Too Many Cooks?

Archie is perhaps the one person Wolfe can never bully; Wolfe values him for that, as well as for his versatility, courage, and loyalty. Although he calls himself Wolfe's "secretary, bodyguard, office manager, assistant detective, and goat," Archie is no flunky: He is a formidable individual in his own right.