Skip to main content Accessibility help
×
Hostname: page-component-7c8c6479df-ph5wq Total loading time: 0 Render date: 2024-03-28T12:49:31.275Z Has data issue: false hasContentIssue false

1 - Problems raised by a definition of life

from Part I - What is life?

Published online by Cambridge University Press:  04 February 2011

Michel Morange
Affiliation:
Ecole Normale Supérieure, Paris, France
Muriel Gargaud
Affiliation:
Université de Bordeaux
Purificación López-Garcìa
Affiliation:
Université Paris-Sud 11
Hervé Martin
Affiliation:
Université de Clermont-Ferrand II (Université Blaise Pascal), France
Get access

Summary

Introduction

Looking for a definition of life raises various issues, the first being its legitimacy. Does seeking such a definition make sense, in particular to scientists? I will successively refute the different arguments of those who consider that looking for such a definition makes no sense, and then propose good reasons to do just that, but also add some caveats regarding what sort of definition is sought. After considering definitions proposed in the past, I will examine various present-day definitions, what they share and how they differ. I will show that the recent suggestion that viruses are alive makes no sense and obscures discussions about life. Finally, I will emphasize two important recent transformations in the way life is defined.

Philosophical and scientific legitimacy of a definition of life

Two questions immediately emerge. Are we seeking a definition of life or a definition of organisms? And what kind of definition should be sought? Two types of definition are, in fact, traditionally distinguished. A definition may aim to give the essential characteristics that causally explain the existence of the category of objects considered. Or a definition may be of more limited scope: to establish a list of properties that are necessary and sufficient to define this category of objects and to distinguish them from objects belonging to other categories. If one adopts the first kind of definition it will be possible to define life. If one opts for the second, one will look for a definition of organisms.

Type
Chapter
Information
Origins and Evolution of Life
An Astrobiological Perspective
, pp. 3 - 13
Publisher: Cambridge University Press
Print publication year: 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×