We moved toward that precipice with a motion as inexorable as that with which time takes us toward our death.

You feel you are creeping up over the edge of a precipice and that this cliff beckons you; worse, that you have a secret desire to fall over its edge into oblivion and that there is no way to stop that fall because you are the precipice.

If we did destroy the planet, it would have irrevocable consequences for the rest of the solar system, and the future for humanity would be dreadful indeed. We would have no planet to live on, and would have perpetrated a terrible crime against ourselves and the other planets. We would end up incarnating on some distant, dark planet, not at all evolved. We would have to start at the beginning, as we were millions of years ago, and take again the long slow climb upwards. It would be unbelievably painful and restrict our evolution for thousands, perhaps millions of years. Why choose that? Why, indeed, choose such an end?

The gradual spread of sterility in seeding plants would result in a global catastrophe that could eventually wipe out higher life forms, including humans, from the planet.

However convergent it be, evolution cannot attain to fulfilment on earth except through a point of dissociation.
With this we are introduced to a fantastic and inevitable event which now begins to take shape in our perspective, the event which comes nearer with every day that passes: the end of all life on our globe, the death of the planet, the ultimate phase of the phenomenon of man.

If you accept the ordinary laws of science, you have to suppose that human life and life in general on this planet will die out in due course: it is a stage in the decay of the solar system... You see in the moon the sort of thing to which the earth is tending – something dead, cold, and lifeless. I am told that that sort of view is depressing, and people will sometimes tell you that if they believed that, they would not be able to go on living. Do not believe it; it is all nonsense. Nobody really worries much about what is going to happen millions of years hence. Even if they think they are worrying much about that, they are really deceiving themselves. They are worried about something much more mundane, or it may merely be a bad digestion; but nobody is really seriously rendered unhappy by the thought of something that is going to happen to this world millions and millions of years hence. Therefore, although it is of course a gloomy view to suppose that life will die out – at least I suppose we may say so, although sometimes when I contemplate the things that people do with their lives I think it is almost a consolation – it is not such as to render life miserable. It merely makes you turn your attention to other things.

If his thinking has been sound, then this world is at the end of its tether. The end of everything we call life is close at hand and cannot be evaded.

If we choose the path of destruction, the planet will continue to descend irreversibly into the Anthropocene Epoch, the biologically final age in which the planet exists almost exclusively by, for, and of ourselves.

I have a big problem with asteroids [...] And so has the rest of the human race. Unless we do something to stop it, sooner or later an impact with an asteroid or a comet will lead to the end of most life on Earth.

It seems impossible to believe that Life, so rare a fruit of the universe, intelligent Life, conscious Life, to which the long course of evolution has been so manifestly leading up all through the long ages, should have no better destiny than a final and hopeless extinction; that this Earth and all the efforts and aspirations of the long generations of men should have no worthier end than to swing, throughout the eternal ages, an empty, frozen heap of dust, circling round the extinct cinder that was once its Sun. If we look backward, we seem to discern clear signs of progress; if we look forward, we discern nothing but the veil. Science is but organized experience, and experience of the future we have none.

Something will happen to Earth eventually, it’s just a question of time. Eventually the sun will expand and destroy all life on Earth, so we do need to move at some point, or at least be a multi-planet species. [...] You have to ask the question: do we want to be a space-flying civilisation and a multi-planet species or not? [...] It's a question of what percentage of resources should we devote to such an endeavour? I think if you say 1 per cent of resources, that's probably a reasonable amount.

The world, as it is now, wants to die, wants to perish — and it will.

The chief cause for the impending collapse of the world - the cause sufficient in and by itself - is the enormous growth of the human population: the human flood. The worst enemy of life is too much life: the excess of human life.

Meanwhile, fierce competition among global self-prop systems will have led to such drastic and rapid alterations in the Earth's climate, the composition of its atmosphere, the chemistry of its oceans, and so forth, that the effect on the biosphere will be devastating. ... We will argue that if the development of the technological world-system is allowed to proceed to its logical conclusion, then in all probability the Earth will be left a dead planet-a planet on which nothing will remain alive except, maybe, some of the simplest organisms-certain bacteria, algae, etc.-that are capable of surviving under extreme conditions.