In the third and final lecture of the 2019 Christmas Lectures, Hannah Fry looks at why maths can fail and asks what the limits of maths are. Watch more Christmas Lectures: http://www.rigb.org/christmas-lectures/watch?utm_source=youtube&utm_medium=social&utm_term=description Hannah Fry is the 2019 Christmas Lecturer. She is an Associate Professor in the Mathematics of Cities at the Centre for Advanced Spatial Analysis at University College London. She works alongside a unique mix of physicists, mathematicians, computer scientists, architects and geographers to study patterns in human behaviour, particularly in an urban setting. Her research applies to a wide range of social problems and questions, from shopping and transport to urban crime, riots and terrorism. https://www.rigb.org/christmas-lectures/2019-secrets-and-lies/meet-hannah-fry?utm_source=youtube&utm_medium=social&utm_term=description This Christmas Lecture was originally broadcast on BBC4 on 28 December 2019. Subscribe for regular science videos: http://bit.ly/RiSubscRibe The Ri is on Patreon: https://www.patreon.com/TheRoyalInstitution and Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter Product links on this page may be affiliate links which means it won't cost you any extra but we may earn a small commission if you decide to purchase through the link.