The term 'hard to arouse' can be summarized by the crossword solution 'STOIC'. Stoicism is an ancient Greek philosophy that emphasizes the development of self-control and fortitude as a means of overcoming destructive emotions. It teaches that one should accept life's hardships without complaint and remain indifferent to pleasure or pain. The STOIC attitude is one of emotional detachment, which allows one to remain calm and composed in difficult situations.