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Why Should We Care if Humans Die Out?

Why should we care if humans die out? Climate activists often claim that future generations have the right to inherit a sustainable world, but it is surprisingly difficult to explain why. BY THOMAS SINCLAIR

We live in apocalyptic times. Global greenhouse gas emissions continue to climb, putting the Earth on track for a catastrophic 3ºC rise above pre-industrial levels by the end of the century if policy continues at its current level. At the same time, we are hacking down, digging up, paving over and polluting more and more of the natural systems upon which we depend. It is not surprising that species extinction rates have leaped to levels not seen for millions of years, with many scientists concluding that the Earth’s sixth mass extinction is now underway.

Meanwhile, the human population is expected to swell to 9.7 billion by 2050. It is not clear that a world of 3ºC heating and irreversible species loss could support anything like that number. Even if humanity is not a casualty of the mass extinction, we seem certain to face a period of miserable retrenchment if we do not change course radically in the next few years. Galvanised by these facts, Extinction Rebellion, Youth Strike 4 Climate and other environmental movements have grown with extraordinary speed, their members fired up with moral indignation at the world’s inaction. However, it proves surprisingly difficult to explain what exactly would be wrong with bequeathing a burning, environmentally exhausted world to future generations.

The roots of the problem were identified more than 30 years ago by the British philosopher Derek Parfit in his influential book Reasons and Persons. As Parfit pointed out, identity is a precarious thing. The particular person you are is the result of a meeting between a particular egg and a particular spermatozoon: had conception taken place only a short time later, it would have been between a different egg and spermatozoon, and you would not have existed. Imagine that after your conception, the second egg and sperm pairing was implanted in an artificial womb, where it grew into a person. That person couldn’t be you – after all, if they attacked you, we wouldn’t say the wounds were self-inflicted.

This means that small differences in circumstances can make very big differences to who exists. Even minor changes in your parents’ behaviour, physiology or environment before your conception would probably have resulted in someone else’s birth rather than your own – someone who, alongside billions of others, will now never exist.

The kinds of change needed to avoid catastrophic climate change are not small: they will involve large-scale social and economic transformation that alters what most people do, where they live, whom they meet and have babies with, and when. If we don’t make the adjustments required to avoid catastrophic climate change and an inhospitable Earth results, the people who inherit the planet will not be the people who would have existed had we made the required adjustments. In fact, the people who inherit the planet will owe their lives to our negligence, for if we had been more provident, they would never have been born. *** This brings us to the crux of the problem. One common argument made against burning fossil fuels and destroying ecosystems is that it causes harm to future generations. Talk of harm invites us to think about how much better off these people would be had we acted otherwise. Yet they would not be better off if we acted otherwise; they would not be at all. Contemporary philosophical thinking about posterity has been dominated by responses to Parfit’s puzzle. The philosopher himself accepted the implication that people who do not yet exist cannot be harmed by what we do now, because our actions will contribute to the creation of different people from those who would otherwise have existed. He also doubted that the puzzle could be solved by appealing to the rights of future people, since their rights against our environmental destruction would effectively be the right not to be born. His solution was to defend “duties of beneficence” that simply require us to bring about as much good as we can in the world, irrespective of who exists in it.

As Parfit’s puzzle seems to show, the imperative not to harm future people does not compel us to stop destroying the environment, because environmental destruction doesn’t harm them. The great advantage of duties of beneficence is that they do tell us that we ought to protect the environment, because a stable climate and rich ecosystems make for a much better world than the one we are currently headed for.

There is, however, a problem with duties of beneficence: they tend to be morally and motivationally weak. The imperative to avoid harm is very stringent, and most people will go far out of their way to comply with it, whereas the positive injunction to improve others’ lives doesn’t have the same power. Murder, for example, is a great deal less common than failure to donate to live-saving charities. When it comes to the environmental crisis, Parfit’s way of framing things may not produce the kind of radicalism that is needed.

Thus we find ourselves faced with a dilemma. We can’t appeal to future generations’ rights against harm to explain why we must change course now. Yet appealing to duties of beneficence doesn’t do justice to the felt urgency of the issue. Is there no way out? The American philosopher Samuel Scheffler has recently proposed a novel solution. He suggests that some of the most powerful reasons to prevent disaster in the distant future may be the interests and concerns of those alive now. *** According to Scheffler, we are already deeply committed to the existence of posterity as part of the procession of human generations in which we, too, take our place. Most obviously, this commitment is exemplified by the despair most people would feel if humanity were faced with imminent extinction, as well as the grief many people do feel in the face of the climate crisis.

But we may also be committed to the survival of humanity through the many meaningful endeavours that presuppose the existence of future generations. Medical researchers and political activists who aim at the improvement of the human condition, for instance, understand that the goals towards which they are working may be attained only after they themselves are gone.

We also engage in activities that give our lives meaning by virtue of their place in an intergenerational enterprise with a history and a narrative of its own, such as the practices of philosophy, literature, sport and religion. Finally, we engage in activities whose value lies in the way they help to transmit wisdom, traditions or achievements across generations, or in the way they enable us to think imaginatively about possibilities for human society. Much education, art and conservation fits this description, as do many festivals and commemorations.

The value of all these endeavours depends on the expectation that humans will survive in conditions conducive to their flourishing long after we ourselves are dead. On Scheffler’s account, we do not think of activism, scholarship or sport as “ephemeral, one-off manifestations of idiosyncratic purposiveness”. Instead, they have their value as parts of projects and narratives that extend over generations, formed for us by our predecessors’ contributions and passed on by us – incorporating contributions of our own – to successors. If Scheffler is right, then we depend much more than we may realise on the survival of humanity far into the future – and not just its bare survival, but its survival under conditions that enable it to flourish and carry on the traditions, collaborations and conversations that give our own lives so much of their meaning and purpose.

We want our lives and the lives of those around us to go well, which means we want our pursuits to be meaningful and the things we care about to survive. And we depend on the well-being of future generations to secure much of what we do and care about, even if we don’t appreciate it now and won’t be around to appreciate it later.

In the face of widespread unwillingness to prioritise the systemic transformation needed to address the climate crisis, activists might draw on Scheffler’s insights in order to show us just how much we ourselves have to lose. Rising greenhouse gas emissions, environmental destruction and mass species extinctions undermine the ability of future generations to secure much of what makes our own lives meaningful. Whatever duties we owe to future generations, we ourselves have an enormous amount at stake in their flourishing.

Thomas Sinclair is fellow and tutor in philosophy at Wadham College, Oxford. This article is part of the Agora series, a collaboration between the New Statesman and Aaron James Wendland, senior research fellow in philosophy at Massey College, Toronto

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