The only thing we know for certain, is that there are no certain things. Change is inevitable. That's why you have to be ready for it. If you aren't ready for it, you'll be left behind when things change. But why resist it? Certain is boring. When things become predictable, it takes the fun out of it. Just ask any stock market investor, any sports player, or any movie-watcher.

Do the unpredictable. Certain is boring.

P.S. I have found an excellent way to train you for the unpredictable. Yamabushido.