In everything that can be called art there is a quality of redemption. It may be pure tragedy, if it is high tragedy, and it may be pity and irony, and it may be the raucous laughter of the strong man. But down these mean streets a man must go who is not himself mean, who is neither tarnished nor afraid. The detective in this kind of story must be such a man. He is the hero, he is everything. He must be a complete man and a common man and yet an unusual man. He must be, to use a rather weathered phrase, a man of honor, by instinct, by inevitability, without thought of it, and certainly without saying it. He must be the best man in his world and a good enough man for any world. ...I'd say that this applies not only to the hard boiled detective but to how we live our own lives.
If there were enough like him, I think the world would be a very safe place to live in, and yet not too dull to be worth living in.
Raymond Chandler, The Simple Art of Murder