Halmos quotes Pólya

If you can't solve a problem, then there is an easier problem you can't solve — find it!

Halmos, P. R. (1985), I want to be a mathematician : an automathography , Mathematical Association of America, , Washington, D.C, p. 76.

(That Pólya.)

Addendum

Yes, I transcribed the quote correctly from Halmos' book. I checked it three times. But Wikipedia says Pólya suggested something different, the logical thing: "If you can't solve a problem, then there is an easier problem you can solve: find it."

I hope this is one of Halmos' jokes. It would be more fun if it is not a typo.