Is it true that, as a class, psychotherapists and other mental health professionals are crazier than average? And that despite their training and experience, they can recognize their own issues less readily than the average nutcase?

— Paul

I defer judgment on whether shrinks don't recognize their problems. On the contrary, there are indications some mental health professionals enter the...

According to the Humane Society, you can extend your dog's life a couple of years by getting him neutered. Are testes really lethal? Does neutering your dog really extend his life? Would the same thing work for men?

— Dave Greenaway

You're not going to want to hear this, Dave. But according to one much-cited study, castrated men live nearly 14 years longer than their intact brethren,...

I'm taking a physics course, and we discussed how objects with hollow cores revolve slower. So I was wondering: Exactly how much dirt would I have to dig out of the ground and move to the surface before I'd notice the days getting longer?

— Mark D. Baragary, Ames, Iowa

Your question inspired my assistant Una to new heights of invention, Mark. She announced you'd given her an idea for an...