What Tom was doing when he made the reference to a "knife fight" was recalling what had been said to him after a climate science hearing in Washington. His notes for his presentation include:
"An aside from a Congressman after a hearing: -You're in a knife fight and need to fight back."
But Chris's Tweet didn't have room for the context. So when the blogosphere's most popular climate-change pseudoskeptic, Anthony Watts, came across the little snippet, his interpretation did not square with the facts. Instead, he attributed the knife comment to Tom, rather than the congressional aide.
I'm not sure I'm wholly convinced by this. If Peterson had quoted the congressman in order to refute or criticise him then that would be one thing. But there is no indication that this was the case - it looks very much as if Peterson was using the quote to illustrate a point.
Peterson's response at Anthony Watts site contains this:
A scientist’s response to both knives and illogic tends to be more science
-Sound, rigorous, peer-reviewed science
-What we do best
-And in the end it will win the day
–Just ask Galileo
So perhaps he was criticising the knife-fight scenario.