This turned out to be a little different from what i had expected or thought that i was reading but, to be fair, Wells completely fulfils his title and the expectation i ought to have had raised, so points to him, not to me. I had, somehow, got it into my head that the book was going to be purely about the cost of the change in lifestyle in the Neolithic age, the agricultural revolution when men stopped being hunter-gatherers and started being farmers. In fact the scope of Wells’ vision is greater than that, as he covers all sorts of consequences stemming from actions other than that revolution (though, in the end, i suppose, it is fair to say that the whole of civilisation stems from that change ~ perhaps that’s how i got my mistaken impression of the book’s scope to begin with), up to the latest, climate change. Overall, i found the book very enjoyable, in scope, style, and content, though i could, perhaps, have done with a little less of Wells travelling to far-flung places at the beginning of each chapter (particularly with regard to his concentration on anthropogenic climate change!). A fascinating subject, and one that probably could (and likely will) be the focus of more books as other writers decide to mine it.