My rating: PG-13 for frequent alcohol use, some language, and a scene of comic violence.
Violence: 2.5/5 - One scene involves a woman's father beating up Arthur. He eventually takes a knife out of a block of cheese. It's all played for laughs. Another man mentions stabbing an intruder as a child.
Language: 3/5 - At least one use of "s--t", plus "sc--w", and milder terms.
Drinking: 4/5 - LOTS. Arthur is a drunk, so it's hard for him to stay away from alcohol. Alcohol is mentioned, too.