Kelley and Dyson On The Future Of Life

Years ago, I read Kevin Kelley's "Out Of Control." The entire book is online here. Fifteen years later I still remember his comments on the resilience of life:

The great secret which life has kept from us is that once born, life is immortal. once launched, it cannot be eradicated. despite the rhetoric of radical environmentalists, it is beyond the power of human beings to wipe the whole flood of life off the planet. Mere nuclear bombs would do little to halt life in general, and might, in fact, increase the nonhuman versions. 

And this about the future of life on the planet:

Why isn’t the earth a solid green from space? Why doesn’t life cover the oceans and fill the air? I believe the answer is that if left alone, the Earth will be solid green someday. The conquest of air by living organisms is a relatively recent event, and one not yet completed. The complete saturation of the oceans may have to wait for rugged mats of kelp to evolve, ones able to withstand storm waves. But in the end, life will dominate; the
oceans will be green.

Whatever happens to me, life will survive. Whatever happens to humankind,. life will survive. There is no way to stop it, no way to eradicate it. And I am part of that unstoppable, ineradicable force. Life on this planet will survive.

And life will probably survive beyond this planet as well:

The galaxy may be green someday too. distant planets now toxic to life won’t always remain so. Life can evolve representations of itself capable of thriving in environments that seem hostile now. But more importantly, once one variety of life has a toehold in a place, the inherently transforming  nature of life modifies the environment until it is fit for other species of life.

Freeman Dyson proposes that life may even extend beyond that. Most of space is empty--with no virtually no gravity, temperatures near absolute zero, and near perfect vacuum: zero-g, zero-T, zero-P. But life is adaptable, even under these conditions:

In an expanding universe, life can adapt itself as the eons go by, constantly matching its metabolism of energy to the falling temperature of its surroundings. Since we are assuming perfect adaptability, the rate of energy metabolism falls with the square of the temperature. This has the consequence that, in an expanding universe, life of any fixed degree of complexity can survive forever upon a finite store of energy. The pulse of life will beat more slowly as the temperature falls but will never stop.

But eventually the universe will grow cold, and matter will stop being matter. Dyson discusses this as well: 

My theoretical physicist colleagues have recently found serious reasons to believe that all matter may be unstable. According to their latest theoretical models, the Grand Unified models of particle physics, the nuclei of all atoms will disappear into positrons and photons and neutrinos with a lifetime of the order of 10³³ years. 

This will be the supreme test of life's adaptability. I do not know whether we can survive without protons.....After the protons are gone, we shall still have electrons and positrons and photons, and immaterial plasma may do as well as flesh and blood as a vehicle for the patterns of our thought. Perhaps the best possible universe is a universe of constant challenges, a universe in which survival is possible but not too easy.  If optimism is the philosophy of people who welcome challenges, then we have plenty of reason to be optimists.

I like his definition of optimism enough to say it again:

If optimism is the philosophy of people who welcome challenges, then we have plenty of reason to be optimists.