Guns, Germs and Steel is a giant book both in the number of pages and in scope. Diamond presents and argues his theory of history here. In contrast to what everyone learns in school (who ruled what where and most importantly when), Diamond is more concerned with big patterns and specifically with the question of why European civilization has repeatedly conquered and subjugated other societies.

His theory is based on the most exciting science of all: geography. His argument is that the status of Europe is ultimately caused by accidents in geography and biology which lead to obvious proximate causes. The very root advantage of Europe and Eurasia is the dominance of east-west axis. Holding everything constant just this single factor makes a huge difference, because crops or animals cultivated in one area of the continent can spread east and west within the same climate zone. It doesn’t mean that all places on the same latitude have exactly the same climate, but they are much more similar to each other than places of the same longitude. While wheat domesticated in the Fertile Crescent could spread to Mediterranean and to Europe easily, quinoa domesticated in the tropics of South America wouldn’t spread to North America. The axis orientation played an important role in migration patterns even before farming because of the similar climate and a smaller role in trade routes and cultural contacts later.

The following cause of different development is the accident of crops and animals suitable for domestication. Diamond shows the differences in potential crops of each region and those which succeeded and then spread mostly along the east-west axis elsewhere. While the Fertile Crescent, Europe and Asia had many successes other continents were disadvantaged by the lack of candidates for the domestication process. The failure to domesticate crops and animals thus doesn’t stem from some fundamental difference between the peoples but in the accident of having more or less suitable initial conditions. Moreover successful steps in domestication and food production lead to food surpluses which enable more domestication and so on, it is a positive feedback loop.

This gets to a place which is generally understood and easy to grasp: food surpluses enable specialization of professions giving rise to other professions, trade and of course bureaucracy. An important factor explored in one of the later chapters is the population density largely enabled by farming: where small groups can self-organize without any explicit structure, large groups where one doesn’t know everyone else naturally develop institutions for the mitigation of conflicts. The difference in organization isn’t caused by difference in intelligence or anything else, but by the necessity.

An important byproduct of sedentary farming in dense populations is the evolution of zoonotic diseases. Domesticated animals give the parasites a large interconnected pool of animals to develop in and the close contact of humans with farm animals (which only recently became less frequent) gave ample opportunities to make the jump to humans. Many such outbreaks had a significant and deadly toll, but on the large scale all those diseases (measels, flu, smallpox) didn’t wipe out whole populations and over the last century and a half became at least manageable if not completely eradicated. However, any time Europeans arrived to a region they haven’t been in close enough contact with before, they brought their diseases with them and thus wreaked havoc on the locals (think of South America). Only because domesticated animals were the source of those diseases and many regions lacked them completely or had significantly fewer domesticated species the diseases didn’t work against Europeans, mostly. There are instances when Europe-originating colonization failed while others succeeded precisely because of resistance to different diseases.

An interesting chapter of the book focuses on tracing the invention of writing which happened in only very few places, namely in the Fertile Crescent, Mexico and China. All these places were already sustaining complex stratified societies dependent on farming surpluses. All other writing systems can be traced to these three locations by borrowing: in some cases only the idea and basic rules carried over (alphabetic, syllabic writing systems, logographies), in others the sets of characters were adapted and repurposed. (There’s a very interesting case of the Cherokee alphabet briefly mentioned; a longer examination of this unique alphabet is in Lexicon Valley No. 22.) Writing of course significantly accelerated development of other technologies and enabled their spread. This process is in turn very much influenced by the population density and connections between different societies which is enabled by agriculture and so on.

The last section of the book traces history of each continent with Diamond’s theory in mind and documents the finer points. On one hand it is a reiteration of the same concepts and ideas as before, on the other I don’t know much about the history of other continents so this excursion was welcome. Probably the most memorable point here is the difference between China and Europe. China has become united early on has stayed that way up until now. While it makes for the biggest nation with a shared language and values, it also makes it more susceptible to whims of the rulers which might hold it back (for example the destruction of ocean-going ships - if that didn’t happen the world could have been colonized by Chinese instead of Europeans), while European fragmentation (not more than half the Europe has been united under a single ruler at any point in the history) means that every time there’s some region pushing in the right direction and whenever a useful technology emerges, it spreads.

Guns, Germs and Steel is an exciting book about history, it goes to the core questions leaving the big men mostly aside. It’s definitely not an easy book to read. It’s packed with information and data but the structure is clear given the scope. I had my copy from the public library and had to borrow it twice (separated by a year in between) to get through it whole. Apparently, a documentary series based on the book exists. I haven’t seen it but it might be a more palatable presentation of the core theory.