I don't have a Koan for you but I can tell you a joke.
Three men are waiting for an interview. The first is called in. The interviewer learns that the first man is a mathematician. As the interview is wrapping up, the inerviewer says "Now before you go, I have one last question. What's 1+1?". "Exactly 2" says the mathematician.
Next, the interviewer calls in the second man, who is an engineer. Towards the end of the interview, again, he says "One last question. What's 1+1?". "Well..." says the engineer "that depends on the accuracy of the original measurement. So I'd say around 2, plus or minus some amount of error".
Finally, the interviewer calls in the third man, who is a lawyer. Again, at the end of the interview, he asks "One final question - what's 1+1?". The lawyer gets up from his seat and goes over the nearby window and closes the shades. He sits back down, and looks plainly into the interviewer's eyes: "What do you want it to be?"
The burning question here is what job are all three of these characters applying for?