Here we have a SETI talk delivered a few years ago on a fascinating topic of communication with ET. An interesting problem when considering a potential contact with ET is what form of communication could be best used. When you think about it, any language that we have here on Earth would be useless. Thus it begs a question of whether any sort of universal language could exist, that could be used to communicate between different civilizations? A possible candidate is the language of mathematics. After all, irrespective of our current understanding of mathematics and physics, certain numbers and concepts are universal (including certain constants such as pi). However, as Keith Devlin discusses in this talk, there are certain complications in using mathematics as the universal language. For more similar videos, visit the SETI channel. Also, here’s a link to the book mentioned in the talk.