Some time back, I had two posts here, with a slightly tongue-in-cheek comment on some ongoing academic campaigns and discussions for attending to small or very unclear risks with potentially very serious negative outcomes - so-called existential risks: here, and here. As reported later, this led to an invitation to debate the issue with Olle Häggström (mathematician and crossdisciplinary futurist), author of this new book on the existential risk issue, at The Institute of Future Studies in Stockholm, and Olle used a number of pages in his book to comment on the points I made in the blog posts. Parallel to all of this, I was invited by Sune Holm at the University of Copenhagen, who's been coordinating a nice series of international workshops on the ethics and philosophy of risk, to contribute to a coming special issue of the research journal Ethics, Policy and the Environment on the theme of the ethics of precaution, an area that readers of this blog know that I'm deeply engaged in since many years. Happy to accept, I took the opportunity to start off from the blogposts and the ensuing debates to clarify what existential risks means for the ethics of precaution, and to attend to some quite difficult theoretical issues left hanging in my own theory of the ethics of precaution and risk, published 5 years ago. I have now submitted my contribution, and the so-called preprint, that is my submitted manuscript before peer review, etc. can be freely read and downloaded here and here.