I really hate blank spots, blank looks, and at the moment, my blank head. (Cheez, all da wit leaks out when da spotlight comes on!) Or, as I expostulated the other day; "AAARRRGGGHH!!! Thing in head no work right now!" (I'll go now...)
We warn the reader in advance that the proof presented here depends on a clever but highly unmotivated trick. -- Howard Anton, "Elementary Linear Algebra"