Po-Shen Loh is a professor of mathematics at Carnegie Mellon University, National Coach of the USA International Math Olympia team, and founder of XB that does online education of basic math and science. He's also the founder of Novid, an app that takes a really interesting approach to contact tracing, making sure you stay completely anonymous. And it gives you statistical information about COVID cases in your physical network of interactions. So you can maintain privacy, very important, and make informed decisions. In my opinion, we desperately needed solutions like this in early 2020. And unfortunately, I think we will again need it for the next pandemic. To me, solutions that require large-scale, distributed coordination of human beings need ideas that emphasize freedom and knowledge.