Assume it can be done

Sometimes the path to success starts with believing that it can be done. There was a brainteaser about 23 prisoners that seemed impossible to solve to me when I heard it but because I knew there was a solution, I thought about it for longer than I would have otherwise and eventually I solved it. 

Assume it can be done. Then your thinking will shift from whether it can be done to how it can be done. And you might get there.