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.
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Notes
- 1.
A good overview of recent advancements and challenges in discovering the origins of life can be found in Orgel (1998), Gasteland et al. (2006), and Shapiro (2007). Boden (2003) has an excellent discussion of how an answer to “What is life?” affects the search for life on other planets. Attempts to create artificial life are reviewed in Adami et al. (1998) and Bedau (2003).
- 2.
The idea that meanings are just concepts in the head is no longer widely accepted by philosophers but, for our purposes here, we can ignore this complication; it doesn’t affect the point that we are making here about definitions.
- 3.
- 4.
We are not overlooking the fact that, in the hammer example, a person must become familiar with hammers and their uses in order to possess the relevant concepts. The point is that a typical English-speaking adult could analyze the concept of hammer without doing any extra empirical (a posteriori) research into the material things that qualify as hammers. By contrast, scientists typically must conduct empirical investigations in order to achieve an understanding of the natural categories (e.g., water) that interest them.
- 5.
Most objects in the universe are in orbit around more than one thing at the same time. For example, Earth’s main orbit is around the sun, but Earth, along with the rest of the solar system, also orbits around the center of the Milky Way, which itself is involved in large-scale movements around the other galaxies in our cosmic neighborhood.
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Cleland, C.E., Zerella, M. (2013). What Is Life?. In: Kampourakis, K. (eds) The Philosophy of Biology. History, Philosophy and Theory of the Life Sciences, vol 1. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-6537-5_2
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