Why do some people call climate change an “existential threat”?
Philosopher Kieran Setiya responds for the MIT Climate Portal

The phrase can refer to a literal threat to humanity’s existence, but also to the danger that unchecked climate change can pose to our ways of life and place in the natural world. "At stake in our reaction to climate how we should feel about our own existence as a species. The answer depends very much on whether we respond to crises like this with grace and compassion and justice, or not.”

— Kieran Setiya, MIT Professor of Philosophy, on the meaning of "existential threat"


In recent years, not only climate scientists but also major world leaders — including the U.S. Secretary of Defense, major American Presidential candidates, and the United Nations secretary general — have labeled climate change an “existential threat.”

What does an “existential threat” really mean, and why are so many people in positions of responsibility now using this phrase?
Kieran Setiya, an MIT professor of philosophy who co-teaches "The Ethics of Climate Change," offers a three-part response. In the worst-case scenarios, climate change is a threat to the continued existence of our species. Secondly: Even if humanity can adapt to a warming world, climate change remains an existential threat to many human cultures, traditions, and languages that will not survive. Finally, the term “existential” also refers to big questions about the meaning of life and humanity’s place in the cosmos. Climate change, Setiya observes, has already changed "our relationship with the planet we live and depend on, which will forever alter the way we feel about human existence."

Full commentary at "Ask A Question," on the MIT Climate Portal

Suggested links

MIT Philosophy

Kieran Setiya's MIT webpage

MIT SHASS Research Portfolio: Health of the Planet

MIT Climate Portal