thanks for your comment. I wish I had an answer for you but us neuroscientist haven’t come up with (far as I know) why when we leave put down a problem we can get the insight to solve it. But it might be related to the playfulness idea. If you are deep into trying to solve the problem your thoughts might be too focused, too limited. And when you take a break your mind opens up and then ‘magically’ come across the solution.

But you make a very interesting point and maybe in the future scientists could explore this issue. Might be difficult to control, for we don’t always come up with the solution when we put down the problem, but worth a try.