When you're a hammer, every problem is a nail.
You draw from your knowledge and experience to find a solution.
I guess the idea is that you strive to be not only a hammer.
I recently learned sinnets, and thus I've put them into every dangling cord I come across at work. I coiled the power cord for the demo Xoom at work. The head of the dept, once he overcame his shock of a seemingly tangled power cord, said: "he has too much time on his hands" and shook his head wistfully.
I was a little embarrassed at first. Now I think he should have been; you want to surround yourself with people that know other things than you, you want your staff to be diverse. This means we're not all hammers and not every problem becomes a nail.