The origin of “death” can be traced back to a time even before life itself began. Although this may sound paradoxical, death appears to have been involved from the very moment life emerged. In contrast, “aging,” which precedes death, seems to have appeared much more recently—and may even be unique to humans. In this lecture, I will explore the biological meaning of both aging and death, and consider how and why they came to be from the perspective of life science.