Explore the intricate design principles of physiological circuits and their aging process in this comprehensive lecture by Uri Alon at the Institute for Advanced Study. Delve into topics such as intrinsic and extrinsic mortality, disease incidence rates, and the mass longevity triangle. Examine the factors influencing lifespan, including gender differences and the optimal timing for antiaging interventions. Investigate the mechanisms of aging, damaged cells, dominance hierarchy, and senescence. Learn about the impact of drugs on the aging process, with a focus on lung senescence and the bystander effect. Gain insights into the Crammers equation and its relevance to aging research. This hour-long talk, part of the Prospects in Theoretical Physics 2019 series, offers a deep dive into the great problems in biology for physicists.