"as humans we really don't know what is really out there" - most challenging idea

I can't decide if this works or not. There is a 150 word limit for the WF supplement question. Does it work? Instead of directly answering the question, I decided to be more objective and tongue and cheek. Be harsh.

What idea most challenges me? Perhaps the idea that as humans we really don't know what is really out there. Essentially, what really are black holes, dark matter? Could there be life on other planets, on Mars or even the Moon? Perhaps the idea of the human mind itself. Could this all really be a dream; what really is consciousness?

Socially, what actually defines us as human beings? What really is the meaning of life? Is ignorance really bliss? Do the laws of physics really apply to EVERYONE? Is Sasquatch real? Where is Waldo?

History is written written by those who have won. Then what is fact and what is hyperbolic fiction? Did Lee Harvey Oswald actually assassinate JFK? Did the Trojan War occur? Did Nero burn Rome? Did Caesar really whisper "Et tu Brute" before he died? Are all men created equal; or are some more equal than others? As tears flood my eyes, why did the holocaust happen; what is the justification for slavery?

Is Dwight Howard really superman and is LeBron James really the King? Whatever happened to OJ Simpson?
Will I get into Wake Forest University?

What idea most challenges me? Kinda redundant IMO. It's like asking 'what do u want for breakfast?' and replying 'What do I want for breakfast? I want blah, blah blah".

Essentially, what really are black holes, dark matter? Could there be life on other planets, on Mars or even the Moon? I wouldn't get into specifics like that. I bet there are scientists that know precisely what black holes are. And could there be life on other planets? Yes... that's already been proven.

Socially, what actually defines us as human beings? What really is the meaning of life? Is ignorance really bliss? Do the laws of physics really apply to EVERYONE? Is Sasquatch real? Where is Waldo? Don't get carried away. And stop answering the question with more questions.

History is written written by those who have won. Then what is fact and what is hyperbolic fiction? Did Lee Harvey Oswald actually assassinate JFK? Did the Trojan War occur? Did Nero burn Rome? Did Caesar really whisper "Et tu Brute" before he died? Are all men created equal; or are some more equal than others? As tears flood my eyes, why did the holocaust happen; what is the justification for slavery?

Is Dwight Howard really superman and is LeBron James really the King? Whatever happened to OJ Simpson?
Will I get into Wake Forest University? More questions? And don't expect the reader to get all your references.

I would scrap it and start over. Try answering the question.

OK I see...
Would it more or less fit the prompt to "I wish I knew..." and use the same ideas, just rework it into that prompt?

You could. But I think it would be more interesting if you stick to one question and then elaborate.