Chill, it’s only been 3 hours. He’s 5 years old so it takes time. Anyways, we started with bijections and cardinality, moved on to countable versus uncountable infinities, Cantor’s diagonal argument, Hilbert’s Hotel, ordinal arithmetic and transfinite induction. I’m trying to get to the aleph hierarchy before bedtime, but he’s really struggling with the axiom of choice and Zorn’s lemma. I think I’ll wait until the morning to cover the continuum hypothesis—don’t want to give him bad dreams, ya know.