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Paradoxes and Infinity

In this class we'll explore several popular paradoxes and attempt to wrap our brains around the world of infinity. For example, we'll discover a hotel that's never full: somehow, this hotel can always add another guest, or two, or three. We'll also run into paradoxes about goats, haystacks, pop-quizzes and more. If you're interested in mind-bending ideas and theories and have a background in basic algebra, this class is for you!

4 days

4 days  


Mon, Tue, Wed & Thurs
Jul 15 - Jul 18
7:30 - 9:00
Jul 15 - Jul 18
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones

AoPS Holidays

There are no classes May 25 ‐ 27, July 4, August 30 ‐ September 2, October 31, November 25 ‐ December 1, and December 21, 2024 ‐ January 3, 2025.


Lesson 1 Paradoxes in Philosophy
Lesson 2 Paradoxes in Mathematics
Lesson 3 Hilbert's Grand Hotel and Infinite Cardinals
Lesson 4 Zeno's Paradox of Dichotomy

I really enjoyed this course. It was at the perfect level of challenge for me, and I learned a lot (and had fun!). I love the amount of detail that is put into the course. I think the amount of homework was just right, enough to cement in the knowledge without any busywork.