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: youtu.be/TgGi1ls1X-0 (on Brady's own channel) See our Zeno's Paradox video at youtu.be/u7Z9UnWOJNY Check computerphile at www.youtube.com/computerphile Website: www.numberphile.com/ Numberphile on Facebook: www.facebook.com/numberphile Numberphile tweets: twitter.com/numberphile Google Plus: bit.ly/numberGplus Tumblr: numberphile.tumblr.com Videos by Brady Haran A run-down of Brady's channels: bit.ly/bradychannels