81
" In this book, therefore, I divide the things that are “impossible” into three categories. The first are what I call Class I impossibilities. These are technologies that are impossible today but that do not violate the known laws of physics. So they might be possible in this century, or perhaps the next, in modified form. They include teleportation, antimatter engines, certain forms of telepathy, psychokinesis, and invisibility. The second category is what I term Class II impossibilities. These are technologies that sit at the very edge of our understanding of the physical world. If they are possible at all, they might be realized on a scale of millennia to millions of years in the future. They include time machines, the possibility of hyperspace travel, and travel through wormholes. The final category is what I call Class III impossibilities. These are technologies that violate the known laws of physics. Surprisingly, there are very few such impossible technologies. If they do turn out to be possible, they would represent a fundamental shift in our understanding of physics. "
― , Physics of the Impossible
88
" It's easy to imagine that, in the future, telepathy and telekinesis will be the norm; we will interact with machines by sheer thought. Our mind will be able to turn on the lights, activate the internet, dictate letters, play video games, communicate with friends, call for a car, purchase merchandise, conjure any movie-all just by thinking. Astronauts of the future may use the power of their minds to pilot their spaceships or explore distant planets. Cities may rise from the desert of Mars, all due to master builders who mentally control the work of robots. "
― , The Future of Humanity: Terraforming Mars, Interstellar Travel, Immortality and Our Destiny Beyond Earth
99
" If we scan all the life-forms that have ever existed on the Earth, from microscopic bacteria to towering forests, lumbering dinosaurs, and enterprising humans, we find that more than 99.9 percent of them eventually became extinct. This means that extinction is the norm, that the odds are already stacked heavily against us. When we dig beneath our feet into the soil to unearth the fossil record, we see evidence of many ancient life-forms. Yet only the smallest handful survive today. Millions of species have appeared before us; they had their day in the sun, and then they withered and died. That is the story of life. "
― , The Future of Humanity: Terraforming Mars, Interstellar Travel, Immortality and Our Destiny Beyond Earth