Human Extinction: A Brief Guided Tour of the Book

200,000 words condensed into 20,000

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Table of Contents

1. Introduction

2. Section 1. History #1—Existential Moods

3. Section 2. Existential Ethics—The Basics

4. Section 3. History #2—Existential Ethics

5. Conclusion

6. Appendix 1

Introduction

The main text of my new book, Human Extinction: A History of the Science and Ethics of Annihilation, is 457 pages long, or around 200,000 words. That’s a lot to read. So, I thought it might be useful to outline some of the key ideas of Part I and Part II. In brief:

Part I is an intellectual history of thinking about human extinction (mostly) within the Western tradition. When did our forebears first imagine humanity ceasing to exist? Have people always believed that human extinction is a real possibility, or were some convinced that this could never happen? How has our thinking about extinction evolved over time? Why do so many notable figures today believe that the probability of extinction this century is higher than ever before in our 300,000-year history on Earth? Exploring these questions takes us from the ancient Greeks, Persians, and Egyptians, through the 18th-century Enlightenment, past scientific breakthroughs of the 19th century like thermodynamics and evolutionary theory, up to the Atomic Age, the rise of modern environmentalism in the 1970s, and contemporary fears about climate change, global pandemics, and artificial general intelligence (AGI).

Part II is a history of Western thinking about the ethical and evaluative implications of human extinction. Would causing or allowing our extinction be morally right or wrong? Would our extinction be good or bad, better or worse compared to continuing to exist? For what reasons? Under which conditions? Do we have a moral obligation to create future people? Would past “progress” be rendered meaningless if humanity were to die out? Does the fact that we might be unique in the universe—the only “rational” and “moral” creatures—give us extra reason to ensure our survival? I place these questions under the umbrella of Existential Ethics, tracing the development of this field from the early 1700s through Mary Shelley’s 1826 novel The Last Man, the gloomy German pessimists of the latter 19th century, and post-World War II reflections on nuclear “omnicide,” up to current-day thinkers associated with “longtermism” and “antinatalism.”

In the book, I call the first history “History #1” and the second “History #2.” For the most part, History #1 shaped the trajectory of History #2, although I argue that this relationality reversed, in a momentous way, at the turn of the 21st century, when ethical considerations about the extreme “badness” of extinction influenced how a number of quite influential people came to think about our collective existential predicament in the universe.

As you can see in this Google Ngram Viewer graph, the frequency of references to “human extinction” increased after World War II, spiked in the 1980s, and since the 1990s has more or less exponentially risen. One of the central aims of the book is to explain why this is the case.