Challenge: Examine enough potential answers to a problem to be confident in one of them. Solution: Tiling trees!
Rationally Speaking, Episode 212: Ed Boyden - http://rationallyspeakingpodcast.org/show/rs-212-ed-boyden-on-how-to-invent-game-changing-technologies.html
Transcript: http://static1.1.sqspcdn.com/static/f/468275/27944421/1531179289400/rs212transcript.pdf?token=TvMGvhsV6k0E6Ao5ze9NYTUURzc%3D
Get Lucky, by Bob Holmes - https://www.sciencedirect.com/science/article/pii/S0262407915310332
Text available here - https://archive.org/stream/New_Scientist_August_22_2015/New_Scientist_August_22_2015_djvu.txt
The Philosophy of Problem Space and Solution Space, by Karen Bachmann - https://blogs.perficient.com/perficientdigital/2011/08/24/the-philosophy-of-problem-space-and-solution-space/
Binary Search Tree (Wikipedia) - https://en.wikipedia.org/wiki/Binary_search_tree