In the book The Big Sleep, by Raymond Chandler, what kind of person is Phillip Marlowe?

Marlowe is very much a loner. He lives alone and works alone. He does not employ a secretary, so most of the time he is alone in his office when he is there. He has a strong sense of independence and a strong sense of honor. Being a private detective should expose him to all sorts of opportunities to make money illicitly. For example, Vivian offers him a lot of money to remain silent about the fact that Carmen killed Rusty Regan, but he refuses to accept it. He is not a happy man or he would not be doing so much drinking; but in this respect he resembles his creator Raymond Chandler, who was an alcoholic. Chandler used to work for the Los Angeles District Attorney, but he tells General Sternwood he was fired for insubordination. Then he adds that he tests very high on insubordination. He is guided more by his feelings than his San Francisco counterpart Sam Spade. Marlowe likes some people and dislikes others, and he takes his feelings about people seriously. For instance, he likes Harry Jones, although Jones is just a grifter. He likes Norris the butler. He likes General Sternwood very much. He dislikes Carmen and Geiger, among others. He gets emotionally involved with clients in "The Big Sleep" and in other novels. Dashiell Hammett's Sam Spade seems relatively cold and selfish by comparison.