Everyone's limits are at a different location for different tasks, and they can be pushed to some extent, but not indefinitely. (If nothing else, people eventually die.) Finding how far your limits in a useful or fun area can be pushed is a worthwhile task as well, and progress is measured by change relative to your past, not someone else's.
So we sit between two tragedies:
On the one hand, we have people who believe genius is magic, and unapproachable, who never work to find what their level is, and never work to push it out.
On the other, we have people who think any level can be attained through hard work, who work themselves into burnout or worse trying to reach goals their lives aren't long enough to attain, and who never appreciate the progress they have made.
I'd say they'd be even better served buying and reading actual science books. Suddenly they could realize they're smarter than they thought.
You first have to teach them analysis, how to break things down and recombine them. A good example here is teaching beginning computer science students how to divide a large, complicated task into a long list of small tasks. Or teaching derivations in basic physics. It's something that's not really formally taught outside of the sciences, and that's a shame.
Honestly I'd recommend the more complex puzzle games. Top recommendation there would probably be SpaceChem: https://www.gog.com/game/spacechem
Solutions to each problem are readily available on youtube, and while it starts off extremely basic the mid and upper level puzzles force you to break things down into distinct parts and have them work together. Best part is there's theoretically thousands of solutions to every puzzle, so even if you crack and look one up, you can then challenge yourself to make a better solution in some way. In fact the game shows you metrics at the end of each puzzle, showing how your solution compared to other players in terms of time, number of parts used, etc.
It's also a lot more entertaining than a textbook as has a pretty awesome soundtrack. :)
> Who are we to say what the author should or shouldn't study? Why is studying a genius a bad thing?
The authors can do whatever they want with their time. But people who buy books and read articles on geniuses would be better served buying and reading science-based books on intelligence. They mostly have all the same advice without the fluff of big names. Also they are actually empirical science, which can't always be said about studies on "famous" people (which to me seem more akin to profiling).
That's not to say you can't enjoy a good biography. But titles like these and what they imply just rub me the wrong way. We're not Einsteins, we'll never be geniuses, and that's fine.