What is the real risk that humanity will become extinct in the next century? It is not a simple academic question, nor a theoretical exercise: it concerns the survival of our species and the generations to come.
Our ability to plan, prevent and prepare for the future may depend on how clearly we address and interpret these numbers. This is why someone seriously asked the question.
One surprise in six will not be pleasant
The discussion about human extinction is not new, but it has recently been reignited by Toby Ord, an Oxford philosopher, who already in 2020 published a book entitled “The Precipice“. In the book, which went a bit quiet due to the pandemic, Ord put forward an estimate that startled many: there is a one in six chance that our species will suffer an "existential catastrophe" in the next century.
A figure so specific and alarming that it has gradually attracted the attention of professionals and the media.
The context of probabilities
Before we dive into the heart of the matter, we need to take a step back and ask ourselves: what exactly do we mean by chance?
The traditional method, called Frequentism, comes from its heritage in dice and card games. For example, we know that there is a one in six chance that a (non-rigged) die will show a three by looking at the frequency of threes in a large number of rolls.
But applying this logic to the likelihood of human extinction presents challenges. After all, an extinction event would be unique; once it happened, there would be no room for repetition.
A century of predictions
One approach might be to look for parallel events to learn from. Ord, in his book, discusses a number of potential extinction events. For example, we can estimate the chances of an extinction-causing asteroid hitting the Earth by looking at how many of these asteroids have hit the Moon over its history.
Jean-Marc Salotti, a French scientist, did just that in 2022, calculating the odds of an extinction-level impact in the next century or so one in 300 million. However, even such an estimate is fraught with uncertainties.
(image: NASA)
Extinct within a century?
There is another way of thinking about probability, called Bayesianism, which focuses less on the events themselves and more on what we know, expect, and believe about them. From this perspective, probabilities are viewed as a classification system.
For example, in Ord's book, there are tables of potential extinction events with his personal estimates of their probabilities. From a Bayesian perspective, we can view these values as relative rankings. And they are all quite reliable: so is there anything to worry about?
A balanced vision
While “one in six” may seem like an alarming number, it is critical to understand the context and methodology behind that figure. This is not a Russian roulette, or something that can happen to us like this, between head and neck (even if the black swans exist). These are probabilities that arise from the simultaneous triggering of various factors, and we can sometimes avoid them just by stopping one of them.
As individuals concerned about the future, say, we must ensure that risks such as climate change and nuclear proliferation receive the attention they deserve. We will make it? But yes.
Correction: but yes, in five cases out of six.
