I got this book looking for a concise history of zero and was disappointed. I think my disappoinment stemmed more from what I was expecting than what this book is. Kaplan guides us through years and years of mathematical development. He gives us a good idea of just how hellish calculations and mathematical relationships must have been before the idea of a null marker as a placeholder. Can you imagine trying to do long division using only roman numerals? Along the way, however, he stops to meander through related ideas or, often, to present his own theories as to how different cultures got to zero from their older systems of measurement. I’m not sure how qualified Kaplan was to present these theories, but they felt like a tangent away from the actual “history” and into idle speculation. A good book, a rich book, but not the book I wanted to read.