A Semantic Discussion

This is something we had to discuss last night at work:

The co-worker's definition of insane: Laughing to yourself (albeit, a little loudly) at a joke somebody told you earlier in the day.

My definition of the insane: Killing the co-worker because he called me insane by bludgeoning him to death with an end table, all the while singing the Canadian National Anthem.

But then, we come from different backgrounds.