The four stages of scientific curiosity, as told by YouTube's favorite physics explainer. First, you're an innocent child wondering about basic planetary motion. Next thing you know, you're a grown adult contemplating Earth's angular momentum. Eventually, you evolve into Homer Simpson levels of scientific inquiry—casually pondering absurd hypotheticals while sprawled on the couch. And finally, you reach peak enlightenment: genuinely wondering what happens when you throw sand into a jet engine. This is the natural progression of anyone who's spent too many nights falling down Veritasium rabbit holes instead of sleeping.