Note: my computer messed up while I was typing this puzzle. My cursor suddenly jumped the end of the thread title, and part of the text that I was typing continued there, then the puzzle posted itself. Yes, this sounds lame, but that's how it happened, see? Do not assume that I accidently typed the answer by mistake.
On a train, Smith, Robinson and Jones are the fireman, brakeman and engineer, but not respectiely. Also aboard the train are three businessmen who have the same names: a Mr. Smith, a Mr. Robinson and a Mr. Jones.
1) Mr. Robinson lives in Detroit.
2) The brakeman lives exactly halfway between Chicago and Detroit.
3) Mr. Jones earns exactly 20,000$ per year.
4) The brakeman's nearest neighbour, one of the passengers, earns exactly three times as much as the brakeman.
5) Smith beats the fireman at billiards.
6) The passenger whose name is the same as the brakemans's lives in Chicago.
The question, as posed in the title of the thread, is: who is the Engineer?