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.