Eight digit mental multiplication isn't a difficult feat. All it requires is you to be able to hold 16 digits in your head. Or more easily, 4 chunks of 4 digits. If you practice and focus on it, you too can relearn how to do long mental arithmetic. But this also requires you're still able to "relax" and empty your mind like a child's, rather than be constricted into an adult's neurotic "I must always be doing something."
Holding conversations in multiple languages? Many bilingual children could join von Neumann, if their parents were as wealthy and involved. Wealth must be present; not only because physical resources give way to access to better tutors and learning material, but also to a tranquility of the mind and soul, that is not found anywhere else but the leisure class (i.e. if you're an upper middle class parent trying to "push" your child into enriching endeavors, all you're teaching is mechanical skill, at the cost of your child's creativity and individual expression -- their soul. Something I've seen too many times).
This is also why anyone who's been in the corporate world for too long, is forever locked out of any great creative or mental achievements: the mental tools needed have atrophied, and it simply is unlikely you'll be able to retrain them, unless some drastic lifestyle change happens (or you do just the right amount of drugs, another improbability).
t. Someone that could also do very long mental arithmetic and "hold conversations" in multiple languages at 6. Going from upper class to being a prole, due to a certain ideological group, has left me painly aware of all the things I've lost. Pieces of the mind and soul that are locked away from the rest; all due to economic circumstance.
Can you explain this?
Well, that's sure a bold statement. I suppose in order to have this discussion, we'd have to agree on a definition of intelligence. For me, it's one's intellectual capacity to learn. Emotionally, physically, mathematically, etc. I'd argue that there is absolutely a thing of "raw intelligence". If we have mentally handicapped and Stephen Hawking, there must be a standard bell curve of intelligence in-between.
However, after re-reading my comment I was a little unclear. When I said: “Intelligence isn’t general it’s specific“ I should have said: “My (And I think others as well) definition of intelligence is how well educated you are in a specific subject. I would never ask someone how smart they are (not useful) but I could ask if they are good at calculus (intelligence in math)”
Maybe a unique perspective or a deeply ingrained and unflappable "lets try this or how does this work?" attitude is all it takes.
Stay curious!
Those people you find so incredibly impressive who have done such worthwhile things? Every single one of them sucks ass at a multitude of things. Every single one of them would see something in your set of capabilities that would astound them.
It takes a vast constellation of capabilities, including yours, to create and sustain our world.