This motto is, of course, a reference to the "General Technics motto" from Stand on Zanzibar, but transposes 'difficult' and 'impossible'. The reason for this is that, in my experience, problems that appear possible are selected for difficulty — because if they were easy they would have been solved already. But the same is not true of problems that appear impossible, so once you have the spark of inspiration that renders them possible, they are likely to in fact be easy.
Another way of putting this would be that unlike genius (as defined by Edison), what I do is 99% inspiration and only 1% perspiration. It's lazy, and it doesn't solve the really hard problems, but it impresses people no end, and it's great fun if you can pull it off!