How do you know that I did not slip and fall on the treacherous ice outside and bruise my arm in that manner?

[He pulls his arm back and tugs his sleeve down in a definite motion. Even high as a kite, he's still loquacious and capable of rational thought. Somewhat.]

Neither you or I wish to have this tired conversation, so why don't we skip it and just say that we've had it? Hm?