Big History, as formalised in this book, is a new area of research but the basic concept dates back to science fiction writer and philosopher-at-large, H G Wells. In his Outline of History, written just after World War I, Mr Wells pointed out that a complete history of humanity would have to reach back in time to the origin of the species and ideally, even further back, to the origin of life and perhaps even further back, to the origin of the universe.

Weaving a single coherent narrative across such a broad sweep of time was impossible then; we simply didn’t know enough. Even today, a century later, it is an amazingly ambitious project. Dr Christian is one among a handful of modern scholars to have actually attempted this.
It involves drawing on an enormous range of disciplines. In order to work as a logical construct, Big History has to serve as a bridge between science and the humanities. A Big Historian must use the historian’s skills to create context and stitch disparate facts together in logical ways. At the same time, a Big Historian must understand science and the philosophy underlying science.

The exposition of any Big History has to be made with great clarity and rigour and the connections between various phases must be made. An understanding must develop of the brevity and ephemeral nature of the entire history of man — indeed of life itself — in the cosmic scale of time. Moreover, unlike conventional history, which deals with relatively small chunks of humanity divided by nation and sub nation (Dr Christian specialised in Russia), Big History deals with the entire species, which means a top-down synthesis of many granular histories.
Above all, in order to be interesting, this must be done in an accessible fashion. It must make sense to laypersons because everyone is a layperson when it comes to Big History. It is simply not possible for any individual to be conversant with all the disciplines involved in creating such a narrative.
Dr Christian’s lectures have become wildly popular. He’s a wonderful public speaker with a knack for simplifying difficult ideas. He is a self-confessed science nerd and that’s a prerequisite because almost the entire narrative is built on science. Big History spans nearly 14 billion years and conventional historical data is available only for the last 5,000 years at best. Our knowledge of the rest is based on science and draws upon disciplines as varied as cosmology, biology, chemistry, geology, meteorology and so on.

This book is built around the architecture of thresholds — a concept that Dr Christian uses to slice Big History into periods that are contextually coherent though vastly unequal in scale. He uses a scale of nine thresholds of increasing complexity. The first eight thresholds pertain to the past and the present; the ninth probes into the distant future, unto the end of the universe.
In cosmological terms, Dr Christian uses the Standard model of physics, and the narrative starts an instant after the Big Bang 13.8 billion years ago. Creation of the expanding universe is Threshold One. Thresholds Two and Three are about star formation (three is ongoing). Threshold Four refers to the formation of the sun and our solar system, some 4.5 billion years ago.
Threshold Five is marked by the earliest appearance of life, 3.8 billion years ago. It covers the following events: Some 600 million years ago, the first large organisms evolved and then the dinosaurs were wiped out 65 million years ago by an asteroid strike. About seven million years ago, the hominid appeared as a lineage distinct from the chimpanzee.
Threshold Six brings us to homo sapiens 200,000 years ago. Threshold Seven starts with the ice age, some 10,000 years ago and continues through to around 1,500 Common Era, when various parts of the world were linked together by voyages of exploration and colonial expansions.

Threshold Eight extends to the current period, with the last 50 years characterised by the “great scientific acceleration”. Threshold Nine speculates that there may be a stable world order perhaps a century in our future and points out that the sun will die some 4.5 billion years from now. Using the conceit of dividing each threshold by a billion, this timeline shows that the human race has existed for only the last 100 minutes of this 13.8 years. Recorded history started less than three minutes ago.
There is an enormous body of popular science works describing the first six thresholds. Dr Christian’s brilliance lies in linking that to Seven and Eight, in the section concisely titled “Us”. This is where he melds science, historical record and speculation to create a playful yet plausible narrative of development from bipedal ape to modern man. How and why we developed large brains, and learnt to store and share knowledge through language is still a mystery. Where we go from here is in the realm of the unknowable. His vision of potential futures is cautious yet optimistic. This book will expand your mental horizons by helping you understand how small a slice of time humanity occupies.


David Christian Allen Lane 368 pages ~699