It is a difficult read - it gets really abstract occasionally and refers to literature I'm not entirely familiar with.
But the idea is worth it. I'll give here the main gist, which is just one aspect of the book.
The book shows how things affect each other. Some people have thought there's just human agency and passive materials to be molded into houses and tools. Others have thought everything is determined only by the material conditions, thinking human psychology, social and historical conditions have nothing to do with anything. Well this book says it all needs combining to get the full picture.
To begin understanding, lets talk about the Neolithic revolution.
15k years ago, everyone was hunter-gathering. Life was simple: the food grows on stuff and runs around, so just pick or shoot and you get your fill. Turns out this is the most energy efficient behavior - low cost, high return. You get to choose the best food to focus on. And humans love it. Wild animals are admired. Killing them is prestigious.
The diet breadth model states that as long as possible, you keep doing just that.
But therein lies the implication - at some point, your favourite food may not be as plentiful, for whatever reason. So when the most energy efficient path is unavailable, you do the second best. You increase the BREATH of your DIET. You start chasing the smaller awkward cross-eyed looking stuff - squirrels and rabbits and whatnot and climbing into deeper bushes for those berries you never cared for. Things you previously ignored.
You're now spending more energy and getting less bang for buck in return.
That's when you think, what if next time I saw my favourite food waltzing or growing around, I just kept it in the village? Let it feed and breed and grow and just skim off the top? That way I could ensure I always have the best dish around and stop bothering with the cross-eyed stuff and weird berries. Back to good times, right?
Not that simple.
You now have a bunch of WILD ANIMALS to manage. First, someone has to always keep an eye on them - shepherding. Then you have to protect it from predators. You probably need a bunch of fences. The male animals start competing, you need to regularly kill them to keep it to a minimum. You also have to take special care for the breeding alpha. Then you have to move em around from graze to graze or they starve. Pregnant ones need a special diet. So instead of doing what YOU want, you're stuck to conforming to what the ANIMAL needs.
And that's all assuming you started with the right species - cattle, sheep, pigs and goats. Turns out people started with frigging gazelles. That didn't stick for long.
All of that takes a lot of energy. So you need to maximize the return. That means more intensive cooking. Gotta spend time splitting bones into small bits to get all that marrow. Gotta boil and cook it for longer to get all the fat into your gut. Need new cooking methods for that. Now people have to sit and mold pots. Pots need fire resistance, so you need to dig deep for mineralized clay. Someone's got to make tools for that. Need to organize labor better. Animal husbandry entails a LOT of work.
Plants are easier, right? Well...
Domesticated plants lose the ability to disperse their seed. That means instead of simply picking or shaking at the ears and collecting the seed that falls off wild plants - you have to cut or pull all the plants out, get them to your camp and just beat them with big sticks - thrashing. Then you have to throw the whole broken mess around until the wind separates the seed from the chaff and other waste - winnowing. And after that PE session is just when the real work begins.
Just as with animals, you're spending more time and energy and so need to maximize bang for buck. You need to grind down the seeds to allow your enzymes to do a better work. That means pestles and mortars and grindstones. Again, someone has to carve them. All that time spent working leaves you less time for wild plants. So as your diet is increasingly onesided, to compensate, you need to get your food into smaller and smaller grains and for that you need bigger and bigger stones - QUERN stones. Google it. Someone has to sit down and chizzle an entire boulder for that. You're not picking it up and moving anymore. Fortunately with all that laboring you're doing, you wouldn't even think about it.
You're now permanently into settled life.
You now need actual buildings where you spend all that time cooking, grinding, crafting, storaging. So now you're digging for much more clay, shaping bricks, propping and maintaining walls. They keep falling apart. Wooden beams for support, but then trees run out. Need bigger bricks, need more mineralized clay, need to dig deeper, need labor management, need better tools, need to plaster the walls regularly for moisture.
Grinding, propping, beating, herding, cooking, all that labor needs laborers - more and more children.
It used to be so much simpler when you just had to throw spears at food...
So you're running faster and faster only to stay in one place. But you're actually falling behind. Skeletal remains start showing signs of stress, deficiencies. People become weaker.
So why even BOTHER? Why didn't people just turn around? As you can see, it was impossible. To build smaller houses would mean less cooking, crafting, would mean less tools, fences, would mean less output from animals, plants, would mean more starvation with a bigger population.
It is a spiderweb of INTERLOCKING connections and DEPENDENCIES, moving hand in hand, thoroughly ENTANGLED.
The author compares it to riding a bike - only the continued momentum holds it up. And just like the rider and bike depend on each other to stay up, so has the domestication syndrome made the plants and animals utterly dependent on human babysitting. And humans in turn have grown utterly dependent on their affording of increased productivty per land unit. It's a double bind.
But it's not just plants and animals. The exact same goes for tools, bricks, houses, everything. It all entails this double bind.
Every time people run into a problem, the fix exerts a cost. The calculation is always this - is it costlier to exert a little more effort, or to overhaul the entire system surrounding it? The former is almost always cheaper.
It's a greedy algorithm - only the locally optimal solutions are sought. Globally, the costs keep compounding. Indefinitely.
Can anything increase indefinitely? That's the question.
I would say the book mirrors Joseph Tainter's Collapse of Complex Societies. While Tainter's book is easier to read, the goals of the books are different. Hoddler's goal isn't simply to show the increasing dependence and complexity, but to actually start incorporating all of the various things that were previously ignored into determining which things affect each other. As we've seen, chemistry, physics, anthropology, carpentry, etc. all play a role. But what I've left out of this review was Hoddler's touching on the social, religious, symbolic, which also fit into this process. And also some systems theory.
Honestly this review doesn't do much justice. There's a lot more to it.