One minus one plus one minus one

Alex Bellos discusses how the Incans used knots in string (Quipu) to record numbers.Check out Brilliant (get 20% off their premium service): https://brillian...

Discussing the brain-bending Grandi's Series and Thomson's Lamp - featuring Dr James Grime.

A little bit of extra footage from the very end of this interview at: http://youtu.be/TgGi1ls1X-0 (on Brady's own channel)

See our Zeno's Paradox video at http://youtu.be/u7Z9UnWOJNY

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