The absolute worst thing you can do in a scene is be apathetic.
Where do the really best laughs come from? Terrific connections made intellectually, or terrific revelations made emotionally.
Every interpersonal situation has a solution in which everyone wins.
The truth is funny. Honest discovery, observation, and reaction is better than contrived invention.
If the whole is to be Art, the parts must not try to be.
No scene is ever about the words being spoken.