Existential risks can be divided into two groups: those that are caused by nature and those that are caused by humans (also known as anthropogenic risks).
Natural risks come from the physical processes of the Earth, sun, and universe at large. These events have always been a danger to all life on Earth, including humanity. Catastrophes like these have caused the extinctions of many other species during Earth’s history.
The fact that we are alive today is evidence that these events are relatively uncommon. However, they’re not as uncommon as we might naively think, since our survival so far creates a bias in our reasoning known as selection bias or survivorship bias.1
Our scientific understanding of the underlying natural processes also helps us create reasonable risk estimates. All together, extinction risk from nature might be as high as one in 1,000 (or 0.1%) during the 21st century. Despite the tremendous progress of human technology so far, there are still many natural events that we cannot control or endure.
What about human-caused risks? A group of experts on the subject estimated that there is a 19% chance that we will destroy ourselves during this century.2 This probability is similar to estimates by other experts.3
Linking these estimates together, we conclude that anthropogenic risks today are about ten thousand times as dangerous as all natural risks combined. Even if these estimates are off by a factor of ten, or a hundred, the result is still effectively the same. The threats of the natural world can’t be ignored, but humanity’s own actions are vastly more dangerous.
Humanity’s actions are now the dominant force shaping our future. Our actions today dictate whether humanity’s potential will be realized or squandered. To improve our chances of success, we will need more people to understand what is at stake, how human reasoning tends to fall short, and the necessity of global coordination.
- Ćirković, M.M., Sandberg, A., Bostrom, N., 2010. Anthropic shadow: Observation selection effects and human extinction risks. Risk analysis 30, 1495–1506. [↩]
- Sandberg, A., Bostrom, N., 2008. Global catastrophic risks survey. Future of Humanity Institute, Oxford University. [↩]
- Matheny, J. G. (2007). Reducing the risk of human extinction. Risk analysis,27(5), 1335-1344. [↩]
3 thoughts to “What will cause human extinction: Natural disaster or human folly?”
A true omnologist 🙂 should take into account that a solar X-flare is a natural risk that is relatively new. Such a solar flare could bring down the Western Empire if the US electrical infrastructure (in bad shape already) is blasted away by an electromagnetic pulse in our direction.