Humanity - the biosphere's best hope?

Human activity often has a negative impact on the Earth's ecosystems. However, according to researchers Karim Jebari and Anders Sandberg, humans are still, in the long run, the best and actually the only hope for ecosystems and the entire biosphere.

The biosphere is the sum of all ecosystems on Earth. Many of them are under significant stress due to human activity, which causes global warming and species extinction. Some people conclude that humans are a threat to the biosphere.

Within ecocentrism, a branch of environmental ethics, ecosystems and the biosphere are considered values in themselves, not just valuable because they can provide something to humans. Within ecocentrism, there are those who believe that it would be best if the human industrial civilization disappeared, and even that humanity as a whole should cease to exist, because humans cause significant environmental destruction.

– Not many people are that radical, but it is common to advocate for de-growth, population control, and the belief that human civilization should be significantly reduced, says Karim Jebari, a philosopher at the Institute for Futures Studies, who co-wrote the article "Ecocentrism and Biosphere Life Extension" with fellow researcher at IFFS Anders Sandberg, who is also a researcher at The Future of Humanity Institute in Oxford. 

The end of life on Earth

The researchers aim to contribute to the discussion about humans and the biosphere by pointing out that humanity, specifically the industrial civilization, is actually the biosphere's best hope.

How so? By considering the long, very long, future. In the long run, various natural processes on Earth and in the solar system will make it impossible for life to exist on Earth. Firstly, Earth's natural inorganic carbon cycle, which regulates carbon dioxide levels and thus temperature, will cease in a few billion years, resulting in the end of life on Earth.

However, a more immediate threat comes from the sun.

– The sun will gradually become hotter, which will also raise the temperature on Earth. In about a billion years, it will be so hot that the oceans will evaporate. At that point, there will be no life left on Earth, says Karim Jebari.

Technological salvation

This is where human civilization comes into the picture. Technology created by humans can theoretically delay these natural processes and thus prolong the lifespan of the biosphere. The technology is currently far away, but it is theoretically possible to influence the inorganic carbon cycle or prevent some of the solar radiation from reaching Earth. However, a prerequisite is that humans continue to exist because only they can develop such technology.

– According to our estimates, a continuing human civilization could extend the life of the biosphere by approximately one billion years. If one considers the biosphere important, there are strong reasons for allowing the technological capacity of human civilization to develop in order to delay the fate awaiting Earth, says Karim Jebari.

An objection is that humans probably won't survive for that long. Humanity could disappear at any time through an existential catastrophe that we ourselves have created. For example through nuclear war, a sufficiently intelligent AI whose goals do not align with human survival, or human-made viruses causing pandemics that kill everyone. There also seem to be natural limits to how long mammal species survive on Earth, roughly 1-10 million years. Therefore, it is highly likely that humans will be extinct in a billion years.

– But it is not necessary for us to survive that long. Many of the technological processes could be automated. From an ecocentric perspective, there would be reasons to argue that humans should survive until these processes can be initiated, says Karim Jebari.

The technology the researchers base their reasoning on may sound like science fiction, but it is rooted in what is theoretically possible.

Exploratory engineering

In futures studies, there is a genre called "exploratory engineering", which involves mapping, as Karim Jebari puts it, "the entire space of possibilities." When discussing time scales of billions of years, there are enormous uncertainties, but the technology is physically possible.

– It is an interesting method to consider all possibilities that are compatible with the laws of physics to see where we end up. Then one can use these thoughts to reason about the present and moral responsibility. What we discuss in the article, such as shields to prevent certain solar radiation, falls within exploratory engineering, but we do not claim that it can be implemented now or even in 100 years. We simply say that it is compatible with the laws of physics and feasible from an engineering perspective, says Karim Jebari.

So - humans as the best hope for the biosphere. However, considering global warming and the fact that we are said to be experiencing the "sixth mass extinction" of species due to human activity, isn't there a greater risk that humans will actually kill the entire biosphere within a billion years, rather than being able to save it from a so-called natural death?

– There is such a risk, but we assess it to be small. Humans have the capacity to eradicate themselves, but no currently known technology can destroy the entire biosphere. Life exists everywhere, and the biosphere as a whole is very resilient. Without humans, the biosphere will undoubtedly perish in approximately one billion years. What we advocate is that we should not dismantle the human industrial civilization. That would completely close the possibility of extending the biosphere's life. Instead, we argue that the least risky option is to allow the human civilization to continue, says Karim Jebari.

The article "Ecocentrism and Biosphere Life Extension" is published in the journal Science and Engineering Ethics and is freely available to read (open access) here >