What Is Life?

Abstract

Distinguishing life from non-life has challenged philosophers at least since Aristotle. In recent years it has taken on increasing scientific importance as researchers seek to understand the origins and extent of life in the universe and explore the possibilities for artificial forms of life. Yet despite spectacular advances in the biological sciences, especially over the last half-century, no consensus among scientists or philosophers has emerged on what life is. In this chapter we describe how this lack of consensus impacts some areas of scientific research, and we discuss what this can teach students about science as a process of discovery. We argue that scientists are not yet in a position to formulate a complete let alone final account of the nature of life, and that for this reason establishing a definition of life can do more harm than good. In order to provide a scientifically compelling answer to the question “what is life?” researchers need access to novel forms of life, and their search should not be constrained by our limited experience with life as we know it on Earth today. In addition to providing an interesting way to present a variety of recent biological discoveries, exploration of these issues is useful in biology education because it demonstrates why science is a fundamentally open-ended and ongoing process of inquiry rather than just a static set of facts and dogmatic principles.