don't be mean Every time you leave a mean comment on the internet, a variable gets accidentally reused in a proof. This leads to much confusion and dismay, not to mention a very troubled indeterminate who will need someone to pay for his or her visits to Sigma Freud.

Seriously–if you don’t have anything nice to say, you’re wasting your time and your fingers’ stamina. I delete mean comments, so only you and I have will ever have the pleasure of reading your well-composed, original, and wryly insightful insults.