I think the world around us gives us all type of CLUEs to our intellectual pursuit. Great thinkers are great observers of hints and clues. Ultimately the physical world (not the bio-sphere or human society) is far simpler than anyone can think of, because of the equilibrium status of the universe. Or read differently the static nature of the universe. The universe is a dead body waiting for eons to be dissected. Complexity is largely suppressed because of the cancelling effect of forces, as well the elimination of complexity by evolution of a closed system. The complexity is decreasing as a function of increasing approximation to an equilibrium.
The trick is to change our human centric mind set and think out our own box. I pointed the natural number conundrum. It is an example of homo sapiens obsession. New type of understanding is needed and can be achieved by shedding unconscious constraints posed upon ourselves.