Seventy thousand years ago – a blink of the eye in evolutionary terms – Homo sapiens was one of several species of human. Clustered entirely in Africa, it had developed only basic language, had no understanding of agriculture, and was yet to domesticate animals. And yet, in the intervening period, Homo sapiens has spread to every continent; developed complex societal structures based on wholly external culture, religion, and myth; and developed technologies that have made it a god in all but name. How did this happen? Why, in the 3.8 billion year history of life on earth, did it happen to us?

Sapiens is Yuval Noah Harari’s impressive attempt to weave a single narrative through the entire course of human history, from the initial evolution of early species of Homo 2.5 million years ago through the development of language and the agricultural revolution, the formation of nation states and the upheaval of the scientific revolution, to the present day.

It charts the accidents of history that have shaped our world, and importantly resists the idea that all progress is automatically good. The agricultural revolution led to more work and more uncertainty; the creation of imagined orders led to oppression and exploitation. Hunter-gatherer societies, in particular, are neither romanticised nor dismissed; for all their manifold disadvantages, people in those societies worked fewer hours, were more resistant to famine and disease, and had a richer and more varied diet.

The accidental nature of these landmark developments – and the puzzling nature of why some changes persisted, despite not being obviously advantageous – is not a new idea; it’s the foundational principle of evolutionary biology, after all. But Harari is particularly good at teasing out the often surprising ways in which all aspects of human society, everything we hold dear, even the existence of society itself, are just the unconscious and unpredictable result of an emergent system. Individual humans, each with incomplete knowledge, each looking out essentially for themselves, perform individually insignificant actions; and yet the cumulative effect is large, and in hindsight patterns emerge.

The overall sense, looking at the long-term view, is of the emergence of order out of chaos: the way that all of these human structures came to be formed out of the anarchy that went before; the ways that humans have become and are becoming more and more unified and homogeneous in their social, economic, and political structures. Along the way there’s an almost bemused detachment from Harari, an amusement at the ways humans have convinced themselves that they’re in control of this process, that they can shape it, that it’s anything but the result of millions of interconnected systems and feedback loops and processes beyond understanding or control.

The book is, as you might expect, at its weakest when it’s predicting the future, rather than summarising the past, but the book follows a neat symmetry: the world before Homo sapiens; our brief moment in the sun; and what the world might look like after we’re gone – whether that’s as a result of our self-destruction, or of our obsolescence as we’re replaced by cyborgs, a technological singularity, or something else. The realisation that our past has been so brief – just 250,000 years since our species emerged, and barely 5,000 years since our culture and society has existed in any recognisable form – makes our future seem so much more fragile, and the threat of self destruction all the more real.

Sapiens a necessarily brief overview, and ventures towards the glib at times. Harari’s “rules” are peppered with exceptions, and his summaries of historical events are as simplistic as the book’s length and subject matter demand. But his narrative races along so speedily, and he threads his theories so neatly through the disparate events of our past, that it’s easy to forgive him; the result is a gripping, engaging and though-provoking jaunt through the depths of our collective history, one that fizzes with excitement and interest.