Why did Timothy try to make Phillip independent in chapter 11 of "The Cay"?

He tried to make him independent for two distinct but related reasons. First, he tried to make Phillip independent as part of his general push to make him stronger. Timothy wanted the best for Phillip, and that included self-reliance. Second, Timothy knew he wasn't going to be around forever, and may have suspected he'd be gone soon. Therefore, for Phillip to survive, he had to be independent.