The basic idea of the book is very old and not original. Social science and philosophy has been arguing about the definition/meaning/origin of debt, money, property right for a long time. He takes a very clear position on it that is clearly based in his ideological believes and then does a running narration of 5000 years of history that all proves his point crossing every social science in the process.
From my perspective as somebody that knows economics, its blatantly clear that he has no respect for economist and has not bothered with history of economic thought beyond finding a few quotes to slander. At the same time its totally clear he has never seriously read the works he seems to despise. It seems that it is his serious believe that economist and apparently the whole history of economics is simply justification for imperialism and slavery.
Not to mention that he is incredibly rude and response with personal attack when people point out that he made some very basic factual errors.
Some of his claims are so incredibly wrong that even somebody who only did the simplest online '101 History of Economic Thought' should not make.
Let me give you an example. Consider this text:
> Voluntary as well as compulsory unilateral transfers of assets (that is, transfers arising neither from a ‘reciprocal contract’ in general nor from an exchange transaction in particular, although occasionally based on tacitly recognized reciprocity), are among the oldest forms of human relationships as far as we can go back in the history of man’s economizing. Long before the exchange of goods appears in history, or becomes of more than negligible importance…we already find a variety of unilateral transfers: voluntary gifts and gifts made more or less under compulsion, compulsory contributions, damages or fines, compensation for killing someone, unilateral transfers within families, etc.*
This was written by an economist in 1892 who according to Graeber only improved on Adam Smith work "by adding various mathematical equations".
The text above was from Carl Menger, one of the most well known economist of the century and one of the founders of modern economics. Not just that, even on that wrote precisely on many of the questions Graeber book addresses. So exactly the kind of person Graeber seems to be wanting to debate and dismiss. The perfect pillar of modern (as in Post-Marginal) economics to shoot down.
Why then would Graeber claim that he only "adding various mathematical equations"? I seems that the only explanation is that he look up the wrong person on wikipedia, as there is another person with the same name who was a mathematician. Nobody who read even an introduction to modern history of economic thought would make that mistake.
He clearly doesn't have a clue who Carl Menger was and clearly has hasn't read his works. He clearly didn't actually study history of economic thought when writing his book. Rather he had preconceived notion and all he needed was a few selective Adam Smith references and dismiss the rest.
At the same time he proudly reference the 1925 'The Gift', to prove how much smarter anthropologists are as they understood the importance of the Gift economy. Compared to economist who according to him only believe in the "Mythical Land of Barter".
He speaks with equal authority about some almost unknown tribal societies, 5000 year old city states that we only have very basic data on and 2000s century politics and modern central banking (that he has borderline no understanding off). Given his very clear and explicit bias and he evident willingness to do selective reading and misinterpretation I much rather read on these topics from actual experts without such a clear bias and explicit political message.