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Topic of Book
Spier overviews all of history from the Big Bang to the present. He also includes theory as to why the universe has developed from simplicity to regions of complexity.
One of the most exciting intellectual developments of the last few decades has been the advent of Big History. Of the books that I have read so far, this one is the best. While most Big History books focus exclusively on a descriptive narrative, this one includes useful theory to tie the entire narrative together.
I highly recommend this book.
- The universe has evolved from extreme simplicity to gradually include regions with greater and greater levels of complexity.
- Complexity means:
- More constituent parts
- Greater diversity of types of those parts
- Interactions between parts within an object
- Differing interactions between different types of parts
- Complexity comes from energy moving through matter under the right conditions. The denser the energy, the more complex the form.
- Complexity can only emerge under certain circumstances:
- the availability of suitable building blocks
- dense enough energy flows
- a great many limiting conditions such as temperatures, pressures and radiation
- Human societies are the most complex and energy dense forms in the known universe.
- As the universe ages, gradually more complex forms are created:
- Sub-atomic particles (protons, neutrons and electrons)
- Solar systems
- Human societies
- Life is evolving faster and to greater levels of complexity because they are driven by a learning process based upon natural selection.
- The complexity of life is fundamentally different from more simple forms of complexity, because it actively harvests matter and energy from outside.
- As soon as more complex organisms had emerged, there was usually no way back. Only rarely have life forms become less complex
Important Quotes from Book
This book is about big history, the approach to history in which the human past is placed within the framework of cosmic history, from the beginning of the universe up until life on Earth today. This book offers a fresh theoretical approach to big history that, I hope, will provide a better understanding not only of the past but also of the major challenges humanity will be facing in the near future.
This book is about big history: the approach to history that places human history within the context of cosmic history, from the beginning of the universe up until life on Earth today. In a radical departure from established academic ways of looking at human history, in big history the past of our species is viewed from within the whole of natural history ever since the big bang. In doing so, big history offers modern scientific answers to the question of how everything has become the way it is now. As a consequence, big history offers a fundamentally new understanding of the human past, which allows us to orient ourselves in time and space in a way no other form of academic history has done so far. Moreover, the big history approach helps us to create a novel theoretical framework, within which all scientific knowledge can be integrated in principle.
Although all the knowledge taught in big history courses is readily available in academia, only rarely is it presented in the form of one single historical account. This is mostly the result of the fact that over the past 200 years, universities have split up into increasing numbers of specializations and departments. Since the 1980s ce, however, academics ranging from historians to astrophysicists have been producing new grand unifying historical syntheses, set forth in books and articles.
Building most notably on the work by US astrophysicist Eric Chaisson (1946 ce–), a historical theory of everything is proposed, in which human history is analyzed as part of this larger scheme.
Like most, if not all large‐scale historical accounts, big history tends to focus on the emergence of developments that cause major changes, most notably new forms of complexity.
Whereas many traditional accounts of human history consist of major events that are placed within a chronological time frame, I am following the approach to history in which important processes play a major role. These include the agrarian revolution, state formation, globalization and industrialization. Within these larger processes, a great many smaller‐scale processes can be distinguished.
The shortest summary of big history is that it deals with the rise and demise of complexity at all scales. As a result, the search for an explanation boils down to answering the question of why all these different forms of complexity have emerged and flourished, sometimes to disintegrate again. Here I will argue that the energy flowing through matter within certain boundary conditions has caused both the rise and the demise of all forms of complexity.
A closer examination of the effects of energy on matter has led scholars to the profound insight that it is energy – and energy alone – that can make matter change. It makes sense, therefore, to define ‘energy’ as anything that can change matter, including making it more, or less, complex.
In the beginning, there would not have been any complexity at all. The further the universe evolved, the more complex some portions of it could become, most notably galaxies. Yet after a rather stormy beginning, most of the universe became, in fact, rather empty and therefore not complex at all. Today, after almost 14 billion years of cosmic existence, the human species is arguably the most complex biological organism in the known universe.
Because no generally accepted definition of ‘complexity’ appears to exist, I decided to tackle this problem by making an inventory of its major characteristics. First of all, there is the number of available building blocks. As more building blocks become available, structures can become more intricate. The same is the case when the variety of the building blocks increases. Clearly, with a greater variety of building blocks, more complex structures can be built. The level of complexity can also increase when the connections and other interactions between and among the building blocks become both more numerous and more varied. On the whole it appears, therefore, that a regime is more complex when more and more varied connections and interactions take place among increasing numbers of more varied building blocks.
At different levels of complexity, different types of building blocks can be discerned. The basic building blocks of ordinary matter are protons, neutrons and electrons. These elementary particles can combine to form chemical elements, which are building blocks on a higher level of complexity. The chemical elements, in their turn, can combine to form molecules, which can be seen as building blocks on an even higher level of complexity. They may jointly form stars, planets and black holes, which are the building blocks of galaxies that, in their turn, may be the building blocks of galaxy clusters. Chemical elements may also combine to form molecules. At a higher level of complexity, a great many different molecules may jointly form cells, which may combine to form individuals that, in their turn, may be the building blocks of society. All these different levels of complexity should be considered relatively autonomous with regard to one another, which simply means that such a particular level of complexity exhibits emergent properties that cannot be sufficiently explained from the properties of a lower level of complexity.
There is another important aspect to complexity, namely sequence… the sequences in which these building blocks are organized can produce considerable levels of complexity, while only a slight change in sequence can wreck this complexity entirely. The sequence of building blocks, and thus information, mostly matters in life and culture.
Forms of greater complexity never suddenly emerge all by themselves out of nothing. Instead, they always develop from forms of lower complexity.
According to many scholars, there are three major types of complexity: physical inanimate nature, life and culture. In terms of matter, lifeless nature is by far the largest portion of all the complexity known to exist in the universe.
All of this cosmic inanimate matter shows varying degrees of complexity, ranging from single atoms to entire galaxies. It organizes itself entirely thanks to the fundamental laws of nature. Whereas the resulting structures can be exquisite, inanimate complexity does not make use of any information for its own sustenance. In other words, there are no information centers that determine what the physical lifeless world looks like.
The second level of complexity is life.
To achieve these elevated levels of complexity, life organizes itself with the aid of hereditary information stored in DNA molecules.
The third level of complexity consists of culture: information stored in nerve and brain cells or in human records of various kinds that is processed and communicated.
During the history of the universe, all these forms of physical, biological and cultural complexity would have emerged all by themselves.
The major question then becomes: how does the cosmos organize itself?
According to the modern view, the emergence of any form of complexity requires an energy flow through matter. Only in this way is it possible for more complex structures to arise. The emergence of life, for instance, must have required a continuous energy flow. But also stars need an energy flow to come into being, while the same happened to planets and galaxies.
All life forms are far from thermodynamic equilibrium. In contrast to lifeless nature, all life forms must harvest matter and energy from outside on a continuous basis. Humans, for instance, have to keep eating, drinking and breathing on a continual basis to keep our complexity going. If we stopped doing so, our complexity would very soon begin to disintegrate. The energy that we ingest serves many purposes: keeping our metabolism going, making plans, moving around, etc
Surprisingly, perhaps, whereas humans may seem vanishingly small compared to most other aspects of big history, we have generated by far the largest power densities in the known universe.
In general, the power densities of life are considerably greater than those of lifeless matter.
Today, most of the energy employed by humans is not used for keeping their bodies going or burning the land but for the creation and destruction of what I will call ‘forms of artificial complexity’: all the material complexity created by humans. These include clothes, tools, housing, engines and machines and means of communication. With the aid of these things, humans have transformed both the surrounding natural environment and themselves.
Artificial complexity is different from naturally emerging complexity in one very important aspect, namely that it is made by animals with purposeful intentions in mind. These artificial forms of complexity could not have emerged all by themselves.
As Eric Chaisson noted but did not systematically elaborate, complexity can only emerge when the circumstances are right. This includes, in the first place, the availability of suitable building blocks and energy flows and, in the second place, a great many limiting conditions such as temperatures, pressures and radiation. Complexity cannot emerge, or is destroyed, when the circumstances are not right. The destruction of complexity is usually caused by energy flows or energy levels that have become either too high or too low for that particular type of complexity…. Apparently, there is a certain bandwidth of temperature levels within which humans can live. Such bandwidths exist not only for all living species but also for rocks, planets and stars. In other words, all relatively stable matter regimes are characterized by certain conditions within which they can emerge and continue to exist. In reference to a popular Anglo‐Saxon children’s story, this will be called the Goldilocks Principle.
The Goldilocks Principle points to the fact that the circumstances must be just right for complexity to exist. It is important to see that these circumstances are often not the same for the emergence of complexity and for its continued existence.
More than any other animal, humans have created a great many Goldilocks circumstances that help them to survive.
I think that the ‘energy flows through matter’ approach combined with the Goldilocks Principle may provide a first outline of a historical theory of everything, including human history.
In the very beginning, the moment of the big bang, there was only undifferentiated matter and energy. But as soon as the universe began to expand and cool down, a first differentiation took place into electromagnetic radiation on the one hand and briefly existing forms of matter on the other hand. In this early period of cosmic history, electromagnetic radiation dominated. During this so-called Radiation Era, very strong radiation existed together with a great many short‐lived matter particles, which emerged out of radiation only to quickly annihilate one another and turn into radiation again.
The expansion of the universe led to a rapid decrease of both temperature and pressure over time. This produced Goldilocks circumstances for the first emergence of matter. The first four minutes, in particular, exhibited by far the greatest and fastest change ever to occur in big history, because during that short period of time all the basic characteristics of the universe emerged.6 This included, first of all, the emergence of the four basic natural forces, the strong (nuclear) force, electromagnetism, gravity and the weak force, as well as the natural constants associated with these forces.
The strong force and electromagnetism shape small‐scale and intermediate‐scale complexity (everything up to the size of rocks a few kilometers in diameter), while gravity shapes everything with a much larger mass (planets, stars and galaxies).
In the early universe, in addition to these four major natural forces, all the elementary particles emerged during the first minutes of cosmic history. These particles subsequently became the building blocks of all further complexity that has existed in the universe.
Electrons are also involved in the formation of chemical bonds that interlink the nuclei of chemical elements. In doing so, they help to keep molecules together. As a result, electrons play a very important role in the emergence of greater complexity.
From this point onward, radiation was no longer dominant. This monumental change signaled the transition from the Radiation Era to the Matter Era.
Apparently, somewhere between 1,000 and 1 million years after the big bang, the temperature of the early universe had dropped to a level that allowed the primordial nuclei, mostly positively charged hydrogen and helium nuclei, to combine with negatively charged electrons to form the first neutral atoms, and a little later also the first small neutral molecules. According to the latest estimates, this would have happened at around 380,000 years after the big bang. By that time, the cosmic temperature would have gone down to 3,000 K. This was the period when the force of electromagnetism became more important than the temperature of the universe in shaping matter.
During the emergence of galaxies, between 700 million and 2 billion years after the big bang, the first stars also emerged. Apparently, at that time Goldilocks circumstances existed that favored star formation. In contrast to galaxies, stars have been forming ever since that time. Clearly, the circumstances for star formation are far less restrictive than those that favored galaxy formation. Indeed, star formation will continue as long as galaxies contain sufficient quantities of hydrogen and helium, the primordial building blocks of stars.
The Goldilocks circumstances in stellar cores favoring nuclear fusion are similar to the conditions that reigned during the Radiation Era. This leads to the profound insight that circumstances that were characteristic of early cosmic history as a whole still exist in stars today, including our sun. A major difference is that the early universe was more or less homogeneous, while stars and their surroundings are not. In other words, while these Goldilocks circumstances existed everywhere for a very short period of time during early cosmic history, they can only be found within stellar cores in the current universe, which take up only a minute portion of cosmic space. Another major difference is that while the infant cosmos changed so quickly that there was hardly any time for nuclear fusion to take place, all stars, even the shortest shiners, live a great deal longer. As a result, stars became the major forges for creating greater complexity at small scales, while the cosmic trash can of interstellar space allowed stars to get rid of their entropy and keep their complexity going.
Stars became the first self‐regulating structures…As a result of this negative feedback loop, stars are self‐regulating, dynamic steady‐state, regimes, which maintain their complexity for as long as they do not run out of nuclear fuel.
In contrast to life, stars and galaxies are complex, but non-adaptive, entities.
The process of nucleo‐synthesis works as follows. The forging of helium out of hydrogen in stellar cores inevitably leads to the depletion of its main fuel supply, hydrogen, and to the formation of helium. In stars that are sufficiently large, after most of the burnable hydrogen has been used up, the unrelenting impact of gravity causes the core to heat to temperatures higher than 108 K. These are Goldilocks circumstances that favor new nuclear fusion processes, in which helium is converted into heavier chemical elements, such as nitrogen, carbon and oxygen. As soon as the helium is burned up, if the star is large enough, its further gravitational contraction will cause the temperature to rise again. This provides Goldilocks circumstances for the emergence of ever heavier chemical elements, all the way up to iron. As was noted earlier, iron is the most stable chemical element, and therefore the heaviest element that can be formed under average stellar conditions.
The galactic habitable zone is characterized by ‘four prerequisites for complex life: the presence of a host star, enough heavy elements to form terrestrial planets, sufficient time for biological evolution, and an environment free of life‐extinguishing supernovae.’
Within the galactic habitable zone, the Goldilocks circumstances for the emergence of complex life include a few more constraints. First of all, if the central star of a solar system were too large, it would burn too fast. As a result, it would not last for a sufficiently long period of time needed for complex life to evolve on its planets. The central star should perhaps not be too small either, because it might not provide enough energy to keep life going. This would very much depend on the proximity of a life‐bearing planet to its central star.
Furthermore, most stars evolve as twins, as double stars. Obviously, planetary orbits around double stars would be rather unstable. As a consequence, the energy flows received from such stars would vary considerably.
Within our solar system, a Goldilocks zone exists that favors life.
Our basic premise is that we are dealing with Earthlike planets with CO2/H2O/N2 atmospheres and that habitability requires the presence of liquid water on the planet’s surface. The inner edge of the HZ is determined in our model by loss of water via photolysis and hydrogen escape [the breakdown of water under the influence of sunlight into its constituent chemical elements oxygen and hydrogen; the hydrogen escapes into space because it is too light to be kept in the atmosphere by the planetary gravitational force]. The outer edge of the HZ is determined by the formation of CO2 clouds
The complexity of a planet such as Earth is caused by at least four major factors: (1) its own gravity, which keeps the planet together; (2) the energy generated deep inside, mostly through the process of nuclear decay of heavy chemical elements such as uranium; (3) the external energy received in the form of radiation from its central star, which mostly influences its surface; and (4) cosmic gravitational effects, including collisions, exerted by other celestial bodies.
Today, Earth is characterized by important Goldilocks circumstances that have been part of our planetary regime for most of its history. First of all, our home planet is more or less the right size. If Earth had been smaller, its weaker gravity would not have been able to retain its atmosphere or liquid surface water, both vital for life. Had Earth been a great deal larger, its resulting stronger gravity would have crushed most living things on land, while more likely than not, any birds that had emerged would not have been able to take off. As a result of its size, Earth’s interior is still hot.
In the second place, Earth has been orbiting the sun at more or less the right distance for more than 4 billion years. As a result, the incoming solar radiation has never been too weak to provide sufficient energy for life to flourish (in which case all Earth’s surface water would have been frozen), nor so strong as to destroy life (for instance, by boiling off all Earth’s water into space). In the third place, Earth is endowed with a large moon, which stabilizes the orientation of Earth’s axis. Without our moon, the angle of Earth’s axis would have changed erratically.
Carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus can all combine into molecules based on covalent bonds.. This polarization of charges is extremely important for building further complexity, because it makes possible a great many forms of weak electromagnetic attraction and repulsion among molecules.
All of life is therefore mostly based on covalent chemistry, although it could not exist without a great many ions that are also dissolved in water. Life’s reactions all take place in a watery environment, because water offers the best possible concentration and flexibility of molecules.
The emergence of life represented, therefore, the emergence of an entirely new mechanism for achieving greater complexity. Unlike stars and galaxies, life forms do not thrive because they use energy that originates from supplies of matter and energy stored within themselves. By contrast, all living things need to continuously tap matter and energy flows from their surroundings to maintain themselves and, if possible, reproduce.
To exist and multiply, life must actively tap matter and energy flows from outside itself on a continuous basis. And because these resources are finite on the good Earth, in the longer run this inevitably means a competition for resources. This insight forms the basis of Charles Darwin’s and Alfred Russel Wallace’s theory of biological evolution, which can be summarized as a competition for matter and energy flows within two types of specific Goldilocks circumstances.
In contrast to lifeless nature, the greater complexity of life involves the active harvesting of matter and energy. This active harvesting costs energy also. In consequence, striking a balance between the costs and benefits of complexity began to play a role as soon as life emerged. For lifeless forms of complexity, such as stars, planets and galaxies, such a balance does not play a role, because they do not harvest matter and energy actively. The emergence of more complex life forms, however, was strongly linked to such a cost‐benefit balance, in which the costs of achieving greater complexity were not greater than the benefits of having it.
This process, in its turn, was driven to a considerable extent by competition within and among species, which helped define what was advantageous for survival and reproduction and what was not.
In contrast to cosmic evolution, which has been slowing down after a very energetic start, biological evolution has been speeding up.
The underlying reason of why both biological evolution and human history have been speeding up can be found in the fact that both have been driven by learning processes. These learning processes first of all concerned the harvesting of enough matter and energy as well as the preservation of one’s own complexity. An important part of this learning process was a continuous re‐evaluation of the cost‐benefit balance of complexity under pressure from Darwin’s and Wallace’s process of natural selection (or nonrandom elimination). This process operates by eliminating both the unfavorable genetic make‐up of a species and its insufficient cultural skills.
Life forms are therefore sometimes called ‘complex adaptive systems.’
As a result of these learning processes, both biological evolution and human history are characterized by positive feedback mechanisms. Biological evolution is based on genetic learning,
The storage of matter and energy for later use appears to be a novel strategy, which is exclusively employed by complex adaptive regimes. It may well be that as life became more complex, their storage regimes also became more complex. Such a trend is apparent in human history, too. These storage regimes can be interpreted as the creation of specific Goldilocks circumstances facilitating the stabilization of irregular matter and energy flows.
Through mutual interactions, the evolving geological processes and the broadening range of living organisms jointly began to shape the surface of our planet and, in doing so, produced ever‐changing and ever more intricate Goldilocks circumstances on the face of Earth. Biologists call such circumstances ‘niches’ when they are occupied by one single species, while the term ‘biome’ is used when these areas comprise larger regions within which many different organisms are making a living.
The complexity of life is fundamentally different from more simple forms of complexity, because it actively harvests matter and energy from outside.
As soon as more complex organisms had emerged, there was usually no way back. Only rarely have life forms become less complex. And if that happened, such species did so within very special circumstances, such as dark caves. t. But there are no cases known to me of complex organisms that spontaneously dissociated into their constituent cells, which subsequently lived and reproduced independently.
Seen from a big history perspective, here we witness a major difference between physical and biological regimes. Whereas all complex life forms exhibit a clear differentiation of form and function within themselves, physical regimes, such as stars, planets or galaxies, can undergo a differentiation of form but not of function. To say, for instance, that individual stars fulfill the function of keeping the entire galaxy together does not make any sense to me. Yet for complex life forms, it makes perfect sense to wonder which functions organs such as hands fulfill for keeping the entire organism going.
The emergence of animals with brains and consciousness was a monumental transition in big history.
Over the course of time, humans have learned to create, manipulate and exploit a great many natural circumstances to their own benefit. In doing so, they have created ever more intricate regimes of Goldilocks circumstances which have, so far, ensured human survival and reproduction. As a result, human history represents a fundamentally new phase in biological evolution.
Humans have been able to do so thanks to their unprecedented ability to process, store and transmit enormous amounts of information as well as to use it for all kinds of purposes and, in doing so, accumulate their knowledge and skills beyond anything other animals have done on our planet. This process is known as ‘culture.’ Whereas many animals exhibit forms of cultural learning, only humans have used it to such a large extent for shaping both their own history and the surrounding natural environment.
The major strength of brains is that they run complex software that can in principle be adapted quickly, according to the circumstances. This makes brainy animals far more flexible and adaptive, and thus far more effective, than other organisms. In contrast to the dominant mechanism for adaptation in biological evolution, in which change comes as a result of genetic variation, humans do it by changing their image of the surrounding world and by adjusting their behavior accordingly. In other words, thanks to culture humans do not have to wait for the emergence of spontaneous genetic change that may help the lucky individuals survive the changing circumstances, while all the others go extinct. Humans only need to change their behavior, not their genes.
Not only are humans unique in the sense that they began to use an ever-widening tool set, we are also the only species on this planet that has constructed forms of complexity that use external energy sources: most notably a great many machines, but also sailing vessels, for instance. This was a fundamental new development, for which there were no precedents in big history. This capacity may first have emerged between 1.5 and 0.5 million years ago, when humans began to control fire.
Around 10,000 years ago, when there were about 1–10 million humans on the globe, they began to profoundly transform their relationship with the natural world through the domestication of plants and animals. In doing so, humans greatly intensified their competition with other species concerning the capture of solar energy. For by domesticating desired plants and animals, as well as by excluding other species that were not considered productive, humans began to control the capture of solar energy that fell on areas where these useful plants and animals grew.
The rise of agriculture can thus be summarized as human efforts that were aimed at concentrating useful bio‐solar collectors (plants) and bio‐energy converters (animals) within certain areas to improve the conversion of solar energy into forms of bio‐energy that were helpful for maintaining or improving human complexity. In doing so, humans created higher gain energy resources out of lower gain ones.
The rise of industrialization in the late eighteenth and early nineteenth centuries implied a fundamentally new way of producing complexity, namely with the aid of machines driven by fossil fuels that consisted of solar energy stored in bio‐molecules that had accumulated in the Earth’s crust over millions of years. In essence, the industrial revolution implied the replacement of muscle, water and wind power by machines powered by fossil fuels. As with biological evolution, human development appears to be driven by the competition for matter and energy. With each major ecological and social transformation, differences in matter and energy use developed as a result of the fact that the pioneers enjoyed a head start. Yet as skills spread, such differences have tended to even out. These developments began with tool use, followed by fire control, the agrarian revolution, state formation, globalization, the industrial revolution and the information revolution.