As Though They Are Real:

The five horsemen of the ecological apocalypse (and the return of hope)

“Caught in the Legend” — Art by Larisa DePalma; concept by DePalma and Rasmus Grønfeldt Winther

The five horsemen of the environmental apocalypse are galloping towards you. Will it be business as usual, or will you try something different? Think quick, there’s not much time. Seventeenth-century Pascal’s wager might help you answer.


What does the future have in store for us? There is no easy way to answer this question. We simply don’t know. Even so, the prospects for Earth, and for many societies, seem bleak. Too many people subject to too many distractions draining too many limited natural resources are causing too many negative impacts. Longstanding natural habitat becomes short-term farmland. Loneliness, alienation, and sadness increase. Health and wealth may also increase for some, but at what cost for the majority in any single country or across the globe?

And whither happiness? How should we measure happiness — and whose happiness? Should individual happiness or satisfaction be the primary metric of success, as dictated by regnant economic and political models? In contrast, as the 2017 World Happiness Report has it, should predictors or explanations of happiness include social support, freedom to make life choices, and generosity?[1] More radically, might we wish to measure aggregate social happiness, locating well-being in societies and communities, as is much more common in non-Western cultures?

Is a desirable future possible? If so, how would we achieve it?

These questions keep me awake at night. They occupied me during the first days of 2018. I had returned from amazing trips to Indonesia and France. Ten days diving and enjoying the Raja Ampat beaches and six days loafing around Paris were sufficient to relax, look inside, share with others, love and feel loved by a flow of old friends and new faces, and open myself to the myriad opportunities life offers. Perhaps all these luxurious opportunities reflect a privileged life. Mea culpa. Opportunities such as this, and the reflection that arises from them, make me a calmer and kinder person, but only if I engage with the opportunity self-consciously and responsibly, knowing I am a microscopic part of an infinite world.

A life of privilege demands a life of responsible contribution, because those with privilege truly have the space and the obligation to reflect. When we engage heart and mind with the existential threat we and Gaia find ourselves in, we must conclude we are ethically bound to do something, for the children of the children of the children we now love. The deepest motivation here is altruistic, not self-serving.


Let us frame climate change as today’s Pascal’s Wager. A 17th-century Catholic, Blaise Pascal asserted two possibilities: God exists or does not. He also outlined two personal choices: I believe in God and will practice religion accordingly; or I do not believe in God and won’t practice religion. A subtler version of the second proposition is that I will engage in religious practices, but maybe not totally believe in God. Pascal argued that action is what ultimately matters.

Table 1. Cost-benefit analysis of Pascal’s Wager. Note that the right-hand column is taken to be much more likely than the left-hand column. Even so, given the extreme cost and benefit differential of the left-hand column, Pascal argued that you should believe God exists.

For Pascal, thinking through this decision rationally should force you to act as if God were real. Why? With even a small probability that God exists, the advantage of going to heaven for eternity (if you act according to God existing) over the dismalness of burning in hell forever (if you act as if God didn’t exist) is so great that this cost-benefit analysis forces your hand (Table 1).[2]


The relation between climate change and our personal beliefs and actions follows a logic similar to Pascal’s Wager. You can choose to live your life as if an environmental existential threat is occurring or as if it is not occurring.

Climate change is just one of what I call the five horsemen of the ecological apocalypse. These are climate change, habitat loss, pollution, overkilling, and invasive species. But are they real? Whether you believe in the five horsemen or not, what will you do about them, if anything?

Empirical and theoretical studies by tens of thousands of researchers show the reality of the five horsemen is extremely probable. Researchers argue about the extent to which they might happen, exactly how and where, etc. But, unlike the case of God in Pascal’s Wager, the five horsemen are almost certainly real and can be identified and measured. For example, scientists recently estimated how much plastic is on the planet right now. The estimate says that if we were to cover the ground ankle-deep (10 inches or 25 centimeters) with all this plastic, it would cover an area the size of Argentina. We have produced about 8 billion tons of plastic since 1950, with only about 10 to 20 percent of this being incinerated or recycled. The vast majority of this plastic has ended up polluting lands and waters.[3]

Table 2. Cost-benefit analysis of The Five Horsemen of the Ecological Apocalypse Wager. Note that the left-hand column is taken to be much more likely than the right-hand column, indeed nearly infinitely so.

On analogy with Pascal’s Wager, let us now move from questions about the five horsemen’s existence to questions about the two choices we each have: do I believe and act as if the horsemen exist or do I neither believe nor act as if they exist? Here are the two choices and rough scenarios that follow (Table 2):

1. Green-life-change. You can believe in the five horsemen and act to combat them. This you can do, whether the horsemen are real, on analogy with Pascal’s Wager, where you can believe and act as if God existed, even if you aren’t sure. Taking the threat of the five horsemen to its logical conclusion, it is the deepest terrestrial existential threat we face. Thus, making this choice would involve acting as if combating the five horsemen were the most important set of actions you could undertake in life, even more important than your desires for and actions towards romantic love, striking it rich, or achieving fame. Living this choice would involve being guided by, and changing your life and actions according to, sustainability criteria or contribution to green living. It would involve radical change — not just recycling and installing solar panels. Conscious consumerism will not save us.[4] As individuals, we will have to join growing social and political movements. Action would need to happen at the highest government levels, to effect change using our best scientific and technological tools.[5] Moreover, in reality, relatively few rich individuals, and many immense corporations contribute exponentially to our crisis, here on Gaia. We must find legal, political, and economic ways to rein them in. Endorsing green-life-change would also determine whether you would start a family, and if so, how; it would shape the content of your work, professional dreams, and aspirations.

2. Business-as-usual. You may claim to believe in and worry about the five horsemen, talk about them at dinner parties, or deny them. Either way, you proceed in your daily life under a business-as-usual model. You continue raising a family, partying, taking vacations, and working as if it were still 1969 or 1983. Life just keeps moving along as normal. You are not bothered with worries about the possibility that your children’s or your children’s children’s ability to flourish is under severe — if not absolute — existential threat.

If you were to really reflect on The Five Horsemen of the Ecological Apocalypse Wager, you would change your life radically and take as seriously as possible the existential environmental threat.[6] I venture to argue this is true whether or not you live a privileged life. Increasingly in free-market capitalism, careers in green and change-inducing industries exist at many levels, on many scales. Perhaps a new job of “green life coach” is possible. Such opportunities may become more likely as societies shift from capitalism to other forms of governance and economic organization, as is likely to happen.[7] Indeed, the green-life-change choice presents many opportunities and growth areas. What do you think you could do? What would you like to do?

The five horsemen of the ecological apocalypse are either true or not. The cost of not acting on them if they are true is immense, indeed, beyond comprehension (in contrast to Pascal’s God hypothesis).[8] To borrow William James’ typology from “The Will to Believe,” the options we have are living rather than dead, forced rather than avoidable, and momentous rather than trivial.[9]

The gain of believing in the horsemen and then acting is, perhaps, not as big as the gain of believing in God and then achieving infinite happiness in heaven. The analogy may break down here anyway. The matrix of existence probabilities and action cost-benefit calculations between the two cases differs, but the logical and analytical framing is the same. For Pascal, God’s existence has a small probability, but acting given God’s existence has a big gain. Not acting given God’s existence implies an immense loss — burning in hell forever. In contrast, the five horsemen’s existence has a high probability, and it is a big problem. Acting on it provides an initially small gain, but later, an immense benefit. In either case, act as if the thing is real, and act dearly and strongly.

Importantly, motivation differs between the two cases. For Pascal’s Wager, individual desires and fears about our own future other-worldly existence motivate us. For the Five Horsemen Wager, caring about others — our children’s children’s children and all future generations — is the source of our motivation.

In Pascal’s Wager, the reason for acting is that the potential benefit is immense, even infinite. In The Five Horsemen of the Ecological Apocalypse Wager, the reason for acting is that the ecological apocalypse is almost certainly real. Each of us can make a small difference as individuals and a large difference with collective, aggregate action. Even one person acting with heroic effort can make a difference for herself and society.

Setting aside the Christian God for a moment, there are important multi-cultural ways to make an analogy between religious belief and action, and the preservation and improvement of the environment. For instance, Buddhist traditions often involve a strong set of practices about the interconnection of all life, reincarnation, and the illusion of the self, the ego and its desires and pains. A Buddhist perspective would see a life focused on empathetic green-life-change as virtuous and, perhaps, even inevitable.


My argument thus far is premised on a risk-neutral attitude, which is the common rational attitude assumption in decision theory. Human beings operate under different rules of rationality in risk-averse contexts. One of two complementary things happens when the probabilities are so small or large that we cannot accept the likelihood of the possibilities we don’t want.

First, if I asked you about winning money if you were willing to eat one tablet from a pool of a million identical tablets, only one of which was cyanide, the others being candy, you would probably play along. If we decreased the pool to 100 tablets, one of which was cyanide, most people certainly would no longer be willing to play.

Second, if I offered you a bet in which I toss a fair coin and you win 30 Euros if it comes up heads, but you lose 20 Euros if it comes up tails, you will almost certainly take the bet. The same payoff matrix massively scaled up will reach the territory of risk aversion. Many people will not make the bet if it is 30 billion Euros to win and 20 billion Euros to lose.

The conjunction of these two risk aversion scenarios is, at bottom, how I view climate change. The odds are so clear and the payoff matrix so enormous, I am not willing to fathom not doing something about it. Upon strong reflection, I will take the Green-life-change over the Business-as-usual choice at any moment. But I formulated the argument within the frame of risk neutrality and regular rationality, to work towards convincing even skeptics who do not accept the five horsemen with nearly absolute certainty of doing something about climate change.

Skeptics can deny the scientific evidence if they must. But study Table 2, particularly the upper-right hand cell. What if we are wrong about environmental catastrophe, and we make this a beautiful world again? Why not endorse the green-life-change option and make this an even more gorgeous world, full of life and wonder, for you and your children’s children’s children? The cost of green-life-change is still relatively low, and the gains relatively large.

Indeed, my argument is further strengthened by the Gayanashagowa, the “Great Law of Peace”, the oral constitution of the Iroquois Confederacy, in which it is stated:

Look and listen for the welfare of the whole people and have always in view not only the present but also the coming generations, even those whose faces are yet beneath the surface of the ground — the unborn of the future Nation.

If we also took the actual votes and agency of future generations into account in our risk analysis calculations, including their perception of their children’s children (and not just our own “now” perspective on future generations, as I do above), the decision is even more massively moved towards Green-life-change. [10]


I am deeply saddened by all the wildlife death, whether on the African savannas, the great North American plains and forests, or the deep blue wilds of the Indian and Pacific Oceans. I feel shock every time I dive on the most beautiful reefs in some of the most remote corners of the Indo-Pacific and see pieces of plastic drift by next to a gracious sea turtle or white-tipped reef shark. To me, all this death and destruction is unbelievable and among the great sins of Homo sapiens. My fear is that continuing to live in our capitalist system, we will simply consume this planet down to its roots. Then where will we live?

We are all connected. We all need to be educated and open our hearts to each other. Therefore, I want to listen to your fears: even defenders of systems I fear (for example, free-market capitalism and the myth of the individual), which I think are transforming beyond recognition, may have legitimate fears too. We can only move forward if we practice a mutual archaeology of fears. Share with me.

My friend Brian Cantwell Smith is an influential philosopher of computer science at the University of Toronto. He was a trail-blazer at Xerox PARC and Stanford University years ago. I first met him in his class where my fellow students and I were the guinea pigs of his wonderful meditation On the Origin of Objects (1998; MIT Press). Professor Cantwell Smith read an earlier version of the present piece and wrote the following to me:

I have a confession, which is that the seeming unraveling of the foundations of humility, human decency, etc. that we witness all over actually worries me more than the climate stuff does, at the moment. Not that I defend that view; but it seems to me that the kind of detached, humane, compassionate world-view that would be a prerequisite for taking climate change seriously is itself eroding at high speed, almost beyond recognition.

I too fear the degrading of empathy and humility. Growing more caring towards other humans (particularly those who most need care — the ill, the poor, the outcast) and towards the many organisms and ecosystems ultimately sustaining us, is part of the change that needs to occur to break the five wild horsemen of the apocalypse. Let us subdue their mad galloping.

[1] Helliwell, John; Richard Layard; and Jeffrey Sachs, eds., World Happiness Report 2017, “Technical Box 2,” p. 17.

[2] A semi-statistical note. We can also think of the cases we are discussing here as Type I (reject a true null) and Type II (accept a false null) errors. We just must correctly establish the null (e.g., God exists) and consider our tolerance and ways, if any, for minimizing these two types of errors in the non-replicable, non-measurable case of God’s existence.

[3] Geyer, Roland; Jambeck, Jenna R; Law, Kara Lavender. 2017. “Production, use, and fate of all plastics ever made.” Scientific Advances 3: 7 (e1700782).

[4] A recent New York Times article resonates with themes in this essay, and exemplifies another potential strategy, civil disobedience:

[5] Three relevant sources here are: Monbiot, George. 2009. Heat: How to Stop the Planet from Burning. New York: South End Press; Hawken, Paul (ed.) 2017. Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming New York: Penguin; Roberts, Callum. 2012. The Ocean of Life: The Fate of Man and the Sea. New York: Penguin (especially Part 2, “Changing Course”). For a thoughtful argument about how our philosophical and personal relationship to basic concepts such as “time” and “now” must also be revisited and revised, see Bjornerud, Marcia. 2018. Timefulness. How Thinking Like a Geologist Can Help Save the World. Princeton, NJ: Princeton University Press.

[6] This apt biblical description of our current environmental situation is borrowed from a quick remark in Roberts (2012), p. 193. The wager framing is unique to this essay.

[7] See Frase, Peter. 2016. Four Futures. Life After Capitalism. London: Verso.

[8] Perhaps a situation analogous to the five ecological horsemen is the nuclear apocalypse scenario. Are you obligated to do something about nuclear disarmament the same way you might be obligated to do something about the five horsemen? Isn’t nuclear war an existential threat? Yes, but it is more difficult to do anything effective about nuclear disarmament because anything that can be done must be done as a high-level political matter. In part, this is also true with the five horsemen, but a whole range of choices, from small to large in the way we each lead our lives, is possible. Also, the significance of the nuclear threat in probability of occurrence or in cost-benefit analysis remains unclear, given the possibility of limited strikes. Because of the realistic low probability of significant nuclear attack, I propose we set aside this analogous situation for the moment.

[9] See title essay in The Works of William James. The Will to Believe and Other Essays in Popular Philosophy, Cambridge, MA and London: Harvard University Press, 1979, edited by Frederick Burkhardt, Fredson Bowers, and Ignas K Skrupskelis; first published in 1897, pp. 3–18.

[10] For a formal model proving this, see Hauser, Oliver P; Rand, David G; Peysakhovich, Alexander; Nowak, Martin A. 2014. “Cooperating with the future.” Nature 511: 220–223. (10.1038/nature13530).