Dat's der bunnies, Helen; it's The Dilbert Future that I was thinking of. Now I've found them, it was Appendix A ("Affirmation techniques") that reads as pure Norman Vincent Peale.

I admit I gave up reading Dilbert cartoons when I realised they were too much like real life for comfort. Sadly, the author of User Friendly (that of which Dilbert is the dark side) seemed to have a crisis of faith or something in the early noughties, and the site has now closed down completely; but that's a separate matter.