
Thought Experiment: The Last Man on Earth
ArticleBig Thinkers + Explainers
BY The Ethics Centre 18 MAY 2021
Imagine for a second that the entire human race has gone extinct, with the exception of one man.
There is no hope for humankind to continue. We know, as a matter of certainty, that when this person dies, so too does the human race.
Got it? Good. Now, imagine that this last person spends their remaining time on Earth as an arbiter of extinction. Being themselves functionally extinct, they make it their purpose to eliminate, painlessly and efficiently, as much life on Earth as possible. Every living thing: animal, plant, microbe is meticulously and painlessly put down when this person finds it.
Intuitively, it seems like this man is doing something wrong. But according to New Zealand philosopher Richard Sylvan (though his argument was published under the name Richard Routley before he took his wife’s name when he married in 1983), traditional ethical theories struggle to articulate exactly why what they’re doing is wrong.
Sylvan, developing this argument in the 1960’s, argues that traditional Western ethics – which at the time consisted largely of variations of utilitarianism and deontology – rested on a single “super-ethic”, which states that people should be able to do what they wish, so long as they don’t harm anyone – or harm themselves irreparably.
A result of this super-ethic is that the dominant Western ethical traditions are “simply inconsistent with an environmental ethic; for according to it nature is the dominion of man and he is free to deal with it as he pleases,” according to Sylvan. And he has a point: traditional formulations of Western ethics have tended to exclude non-human animals (and even some humans) from the sphere of ethical concern.
Traditional formulations of Western ethics have tended to exclude non-human animals (and even some humans) from the sphere of ethical concern.
In fairness, utilitarianism has a better history with considering non-human animals. The founder of the theory, Jeremy Bentham, insisted that since animals can suffer, they deserve moral concern. But even that can’t criticise the actions of our last person, who delivers painless death, free of suffering.
Plus, most versions of utilitarianism focus on the instrumental value of things (basically, their usefulness). Rarely do we consider the fact that when we ask “is it useful?” we’re making an assumption about the user – that they’re human.
Immanuel Kant’s deontology begins with the belief that it is human reason that gives rise to our dignity and autonomy. This means any ethical responsibilities and claims only exist for those who have the right kind of ability: to reason.
Now, some Kantian scholars will argue that we still shouldn’t treat animals or the environment badly because it would make us worse people, ethically speaking. But that’s different to saying that the environment deserves our ethical consideration in its own right. It’s like saying bullying is wrong because it makes you a bad person, instead of saying bullying is wrong because it causes another person to suffer. It’s not all about you!
Sylvan describes this view as “human chauvinism”. Today, it’s usually called “anthropocentrism”, and it’s at the heart of Sylvan’s critique. What kind of a theory can condone the kind of pointless destruction that the Last Man thought experiment describes?
Since Sylvan published, a lot has changed – especially with regard to the animal rights movement. Indeed, Australian philosopher Peter Singer developed his own version of consequentialism precisely so he could address some of the problems the theory had in explaining the moral value of animals. And we can now pretty easily say that modern ethical theories would condemn the wholesale extinction of animal life from the planet, just because humans were gone.
But the questions go deeper than this. American philosopher Mary Anne Warren creates a similar thought experiment. Imagine a lab-grown virus gone wrong, that wipes out all human and animal life. That would be bad. Now, imagine the same virus, but one that wiped out all human, animal and plant life. That would, she thinks, be worse. But why?
What is it that gives plants their ethical status? Do they have intrinsic value – a value in and of themselves, or is their value instrumental – meaning they’re good because they help other things that really matter?
One way to think about this is to imagine a garden on a planet with no sentient life. Is it better, all things considered, for this garden to exist than not? Does it matter if this garden withers and dies?
Or to use a real-life example: who suffered as a result of the destruction of the Jukaan Gorge – a sacred site to the Puutu Kunti Kurrama and Pinikura people? Western thought conceptualises this as wrong to destroy this site because it was sacred to people. But for Indigenous philosophical traditions, the destruction was a harm done to the land itself. The land was murdered. The suffering of people is secondary.
Sylvan and others who call for an ecological ethic, believe the failure for Western ethical thought to conceptualise of murdered land or what is good for plants is an obvious shortcoming.
This is revealed by our intuition that the careless destruction of the Last Man on Earth is wrong, even if we can’t quite say why.
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BY The Ethics Centre
The Ethics Centre is a not-for-profit organisation developing innovative programs, services and experiences, designed to bring ethics to the centre of professional and personal life.
7 Comments
I would say the deliberate extinction of all life is actually the correct ethical decision to make. It prevents all future suffering, and prevents an alternate species from rising to fill the vacuum that humans once occupied.
The only real problem is if it is incomplete – all life needs to be eradicated, or the act of attempting is essentially pointless, as life will continue to proliferate. Unfortunately universe-wide sterilisation is likely impossible, except in an end-of-the-universe scenario.
In short the conclusion of the article is flawed, as while it condemns a human-centric world view, it arbitrarily upholds a life-centric world view as somehow better.
Who can say a living organism holds more value than a lifeless rock?
I would say a lifeless rock is a more favourable situation, as a lifeless rock cannot suffer, or perpetuate a cycle of suffering.
ReplyThat view sounds like a desire to eliminate life because it would eliminate suffering, right? Is that your view of your life and the life around you, or are you merely responding to what you see as the most ethical response in this thought experiment? If the former, can I suggest reaching out to a mental health service like Lifeline – there is always hope for a better life. If the latter, could you explain the difference between the real world vs hypothetical scenario?
ReplyArticle by big thinkers & explainers? This text makes no sense at all: ‘But for Indigenous philosophical traditions, the destruction was a harm done to the land itself. The land was murdered. The suffering of people is secondary.’ If someone is happy to blow up a non ‘sacred’ site, then according to that excerpt that land would be ‘murdered’ to, and people would be against that as well, but they arnt, & apparently it’s just a by product of the mining process. Pretty bad real life example.
ReplyI thought similarly when I read this. I’ll admit there’s a lot I don’t know about indigenous knowledge, and call me cynical, but it seems to me that the very fact that some places are deemed “sacred” while others aren’t seems to be prima facie about the utility provided by those places to humans (Indigenous people). I.e. anthropocentrism. Can anyone provide another view?
ReplySimply put, earth is a pretty blue ball spinning through vast space and the environment on this ball is what its all about. Everything comes from there. As the top order predictor who have the ability to make decisions, we, humans, who have developed the concept of ethics, are bound to accord full ethical status on to the environment on this pretty blue ball hurtling through the unknown.
ReplyI have a fundamental disagreement with the idea that no-one is harmed. Firstly, while he is the last human on Earth, he still harms himself with every destructive act. Not moral harm, but physical harm to himself. He is making his own death quicker through this action – and if human life is important, even his would be.
The environment sustains human life. It is a fundamental enabler of our lives. Destroying it harms every current and future human.
More than that, though, I think the environment is worthy of its own value – and arguably, this has already been valued by economists (though not accounting for negative externalities, because money seems to get more moral and legal value…).
Humans are not separate from nature. Our capacity for reason (despite some not able or willing to use that capacity) does not make us separate – we are as interconnected with the Earth as any other species on the planet. Any species in an inappropriate place, in unsustainable numbers can be a problem for the planet – this isn’t limited to mouse plagues in NSW.
ReplyThe environment should be given ethical status because sadly it is at our mercy.
That Western ethical traditions hold that ‘nature is the dominion of man and he is free to deal with it as he pleases’ is entirely a religious construct as the ‘man’ it refers to is merely interpreting a book (the Bible).
But the concept of a god is a man-made construct which should have no right to determine what happens to nature or the environment which holds no such belief. By holding the view that humans have dominion over the earth and having destroyed and continuing to destroy the environment, it means that we have a responsibility to protect it and give it ethical status.
Join the conversation
Why should the environment be given ethical status?