---
title: "Ethics of terraforming"
chunk: 1/3
source: "https://en.wikipedia.org/wiki/Ethics_of_terraforming"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:24:29.448939+00:00"
instance: "kb-cron"
---

The ethics of terraforming has constituted a philosophical debate within biology, ecology, and environmental ethics as to whether terraforming other worlds is an ethical endeavor.

== Support ==
On the pro-terraforming side of the argument, there are those like Robert Zubrin and Richard L. S. Taylor who believe that it is humanity's moral obligation to make other worlds suitable for Terran life, as a continuation of the history of life transforming the environments around it on Earth. They also point out that Earth will eventually be destroyed as nature takes its course, so that humanity faces a long-term choice between terraforming other worlds or allowing all Earth life to become extinct. Dr. Zubrin further argues that even if native microbes have arisen on Mars, for example, the fact that they have not progressed beyond the microbe stage by this point, halfway through the lifetime of the Sun, is a strong indicator that they never will; and that if microbial life exists on Mars, it is likely related to Earth life through a common origin on one of the two planets, which spread to the other as an example of panspermia. Since Mars life would then not be fundamentally unrelated to Earth life, it would not be unique, and competition with such life would not be fundamentally different from competing against microbes on Earth. Zubrin summed up this view:

Some people consider the idea of terraforming Mars heretical—humanity playing God. Yet others would see in such an accomplishment the most profound vindication of the divine nature of the human spirit, exercised in its highest form to bring a dead world to life. My own sympathies are with the latter group. Indeed, I would go farther. I would say that failure to terraform Mars constitutes failure to live up to our human nature and a betrayal of our responsibility as members of the community of life itself. Today, the living biosphere has the potential to expand its reach to encompass a whole new world. Humans, with their intelligence and technology, are the unique means that the biosphere has evolved to allow it to make that land grab, the first among many. Countless beings have lived and died to transform the Earth into a place that could create and allow human existence. Now it's our turn to do our part.
Richard Taylor more succinctly exemplified this point of view with the slogan, "move over microbe".
Some human critics label this argument as an example of anthropocentrism. These critics may view the homocentric view as not only geocentric but short-sighted, and tending to favour human interests to the detriment of ecological systems. They argue that an anthropocentrically driven approach could lead to the extinction of indigenous extraterrestrial life, or interplanetary contamination.
Martyn J. Fogg rebutted these ideas by delineating four potential rationales on which to evaluate the ethics of terraforming—anthropocentrism, zoocentrism, ecocentrism, and preservationism—roughly forming a spectrum from placing the most value on human utility to placing the most value on preserving nature. While concluding that arguments for protecting alien biota can be made from any of these standpoints, he also concludes with an argument, similar to Zubrin's, that strict preservationism is "untenable", since "it assumes that human consciousness, creativity, culture and technology stand outside nature, rather than having been a product of natural selection. If Homo sapiens is the first space faring species to have evolved on Earth, space settlement would not involve acting 'outside nature', but legitimately 'within our nature'."

== Criticism ==

Strong ecocentrists like Richard Sylvan feel there is an intrinsic value to life, and seek to preserve the existence of native lifeforms. This idea is usually referred to as biocentrism. In response to these objections, weak anthropocentrism incorporates biocentric ethics, allowing for various degrees of terraforming.
Christopher McKay strikes a position between these two, what may be termed weak ecocentrism, proposing that an entire biosphere of alien life, even if only microbial life, has far more value than individual microbes, and should not be subject to interference by Earth life. However, he also proposed that it would be valuable and desirable to terraform a planet to nurture the alien life, to allow it to thrive as well as to exhibit a broader range of behavior for scientific study, and that such activity is ultimately justified by the utilitarian value to humans of being able to study and appreciate the still somewhat undisturbed alien life. McKay put his views in these words: