How did Homo sapiens manage to cross this critical threshold, eventually founding cities comprising tens of thousands of inhabitants and empires ruling hundreds of millions? The secret was probably the appearance of fiction. Large numbers of strangers can cooperate successfully by believing in common myths. Any large-scale human cooperation – whether a modern state, a medieval church, an ancient city or an archaic tribe – is rooted in common myths that exist only in people’s collective imagination.

Homo sapiens is a storytelling animal that thinks in stories rather than in numbers or graphs, and believes that the universe itself works like a story, replete with heroes and villains, conflicts and resolutions, climaxes and happy endings. When we look for the meaning of life, we want a story that will explain what reality is all about and what my particular role is in the cosmic drama. This role makes me a part of something bigger than myself, and gives meaning to all my experiences and choices.

Over the past 10,000 years, Homo sapiens has grown so accustomed to being the only human species that it’s hard for us to conceive of any other possibility. Our lack of brothers and sisters makes it easier to imagine that we are the epitome of creation, and that a chasm separates us from the rest of the animal kingdom. When Charles Darwin indicated that Homo sapiens was just another kind of animal, people were outraged. Even today many refuse to believe it. Had the Neanderthals survived, would we still imagine ourselves to be a creature apart? Perhaps this is exactly why our ancestors wiped out the Neanderthals. They were too familiar to ignore, but too different to tolerate.

Tolerance is not a Sapiens trademark. In modern times, a small difference in skin colour, dialect or religion has been enough to prompt one group of Sapiens to set about exterminating another group. Would ancient Sapiens have been more tolerant towards an entirely different human species?

Over the past 150,000 years, Homo sapiens evolved in a world that was “local and linear,” but today’s environment is “global and exponential.

Tolerance is not a Sapiens trademark. In modern times, a small difference in skin colour, dialect or religion has been enough to prompt one group of Sapiens to set about exterminating another group. Would ancient Sapiens have been more tolerant towards an entirely different human species? It may well be that when Sapiens encountered Neanderthals, the result was the first and most significant ethnic-cleansing campaign in history.

The problem holding everything up thus far is that Homo sapiens is an innately dysfunctional species. We are hampered by the Paleolithic Curse: genetic adaptations that worked very well for millions of years of hunter-gatherer existence but are increasingly a hindrance in a globally urban and technoscientific society. We seem unable to stabilize either economic policies or the means of governance higher than the level of a village.

There is some evidence that the size of the average Sapiens brain has actually decreased since the age of foraging.5 Survival in that era required superb mental abilities from everyone. When agriculture and industry came along people could increasingly rely on the skills of others for survival, and new ‘niches for imbeciles’ were opened up. You could survive and pass your unremarkable genes to the next generation by working as a water carrier or an assembly-line worker.

Not only rationality, but individuality too is a myth. Humans rarely think for themselves. Rather, we think in groups. Just as it takes a tribe to raise a child, it also takes a tribe to invent a tool, solve a conflict, or cure a disease. No individual knows everything it takes to build a cathedral, an atom bomb, or an aircraft. What gave Homo sapiens an edge over all other animals and turned us into the masters of the planet was not our individual rationality but our unparalleled ability to think together in large groups.1

Evolution has made Homo sapiens, like other social mammals, a xenophobic creature. Sapiens instinctively divide humanity into two parts, ‘we’ and ‘they’.

It was as if a vital evolutionary advantage had been bestowed centuries ago on those members of the species who lived in a state of concern about what was to happen next. These ancestors might have failed to savour their experiences appropriately, but they had at least survived and shaped the character of their descendants, while their more focused siblings, at one with the moment and with the place where they stood, had met violent ends on the horns of unforeseen bison.

Homo sapiens [are] a tiny twig on an improbable branch of a contingent limb on a fortunate tree.

Human history can be viewed as a slowly dawning awareness that we are members of a larger group. Initially our loyalties were to ourselves and our immediate family, next, to bands of wandering hunter-gatherers, then to tribes, small settlements, city-states, nations. We have broadened the circle of those we love. We have now organized what are modestly described as super-powers, which include groups of people from divergent ethnic and cultural backgrounds working in some sense together — surely a humanizing and character building experience. If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. Many of those who run the nations will find this idea unpleasant. They will fear the loss of power. We will hear much about treason and disloyalty. Rich nation-states will have to share their wealth with poor ones. But the choice, as H. G. Wells once said in a different context, is clearly the universe or nothing.

For the entire course of evolution leading from our primitive mammalian forebears of a hundred million years ago to the single lineage that threaded its way to become the first Homo sapiens, the total number of individuals it required might have been one hundred billion. Unknowingly, they all lived and died for us. (21)