There are always some human beings who live to be a hundred. More do so today than ever before, but there have always been some… It comes as a shock to realise that the whole of civilisation has occurred within the successive lifetimes of sixty people – which is the number of friends I squeeze into my living room when I have a drinks party. Twenty people take us back to Jesus, twenty-one to Julius Caesar.
If history were a footbal field, all of human history would occupy an area the size of my hand.
Imagine living, in order of birth, through the life of every human being who has ever lived… Your life lasts for almost four trillion years in total. For a tenth of that time, you’re a hunter-gatherer, and for 60 percent you’re an agriculturalist. You spend a full 20 percent of your life raising children, a further 20 percent farming, and almost 2 percent taking part in religious rituals. For over 1 percent of your life you are afflicted with malaria or smallpox. You spend 1.5 billion years having sex and 250 million giving birth. You drink forty-four trillion cups of coffee. As a colonizer, you invade new lands; as the colonized, you suffer your lands taken from you. You feel the rage of the abuser and the pain of the abused. For about 10 percent of your life you are a slaveholder; for about the same length of time, you are enslaved.
But now imagine that you live all future lives, too. Your life, we hope, would be just beginning. Even if humanity lasts only as long as the typical mammalian species (one million years), and even if the world population falls to a tenth of its current size, 99.5 percent of your life would still be ahead of you. On the scale of a typical human life, you in the present would be just five months old. And if humanity survived longer than a typical mammalian species—for the hundreds of millions of years remaining until the earth is no longer habitable, or the tens of trillions remaining until the last stars burn out — your four trillion years of life would be like the first blinking seconds out of the womb.