I agree with this. Though I would argue that at this point, it's not just the Keynesians but all of mainstream economics (unless Saifedean means to say that all mainstream economics is Keynesian). Modern economics is obsessed with "scientific and mathematical rigor", at the expense of more historical and dialectical perspectives.

It's at the point now where you can go through an Economics PhD program and not even take a class in the history of economic thought. [Source: I went through an Economics PhD program without taking a class in the history of economic thought.]

I'm all for mathematical and scientific rigor. Mathematical models and econometric analysis have their place. But I believe that in mainstream economics, the marginal benefit of more "rigor" has diminished below its marginal cost.

I'll give you an example of how this plays out. For certain fields, especially macro, every paper needs some kind of mathematical model. And not only do you need a model, you need to be able to prove the existence and uniqueness of its equilibrium. Proving existence and uniqueness of equilibria in a complex system is very difficult. So what do the economists do? They make simplifying assumptions that make the model less realistic but easier to solve.

In other words, the need for mathematical proof takes priority over the realism and predictive power of the model. To go even further, the simplifications are often made so that the model can explain at least one aspect of reality--at the expense of other aspects. This renders the overall predictive power of the model less, as it is a case of overfitting to the phenomenon that the model seeks to explain.

Thanks for the review. I might pick up this book as well, once I clear through the rest of my reading backlog.