Assume you’re trying to solve a problem that others also want to be solved, e.g., a problem that, if unsolved, negatively impacts a lot of people.
If the solution were obvious, it would be solved. So you know the solution isn’t obvious. That means you should look in non-obvious places. In practice, that might just mean looking where others aren’t looking for some reason — i.e., some failure in the ideas market.
But once you’ve found a non-obvious place to look, the best solution is probably among the more-obvious-seeming candidates.
Example: Solution requires thinking about problem from the perspective of two disjointed academic fields. Very few people think about anything from the perspective of those disjointed fields due to some weird aspect of how those fields developed — thus it’s a non-obvious place to look. But once you’ve started looking there, it’s probable that connecting the most-basic ideas between those fields is all you need.
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