Disclaimer: I was sent a free review copy of this book.
OK, the blog post:
The basic idea of this book ("Through the Language Glass: Why the world looks different in other languages" by Guy Deutscher) is to examine the premise that the language we speak influences how we interpret the world. The primary approach throughout is an analysis of how languages describe color. I've found that many people aren't really interested in color terms cross-linguistically because they assume that such analysis is merely providing translations. Of course (and as this book points out), languages in fact vary widely in how many color terms they have. Blackfoot has one word for blue/green, while Arabic has completely separate words for dark blue and light blue. I found the first half of this book to be the most compelling, providing a lot of history about how philologists and then linguists approached the question of color across cultures. These approaches began as mostly racist caricatures and progressed to the seminal Berlin & Kay work that established a (mostly) definite order of color acquisition that with very few exceptions predicts which color terms a language will have based on its number of colors terms. A language with just two colors will divide them into dark and light, and a language with three colors will always have red as the third color. (While there are exceptions to some of the predictions, the one just stated is as far as I know exceptionless. I would be very interested if anyone knows of any exceptions -- languages with only three basic color terms that do not include red as one of the color terms.) This part of the book is written clearly enough and provides enough helpful examples that I actually used it in my own teaching several times, as a content unit about colors for ESL classes.
I was really disappointed in that one chapter, but once I got through it, I did enjoy the rest of the book. That last part of the book finally delves into the science that I was perhaps most interested in from the start, comparing how languages use color terms and offering numerous summaries of experiments showing that how a language divides up colors can influence how quickly speakers perceive differences between colors. The author's most compelling point is that while language does not dictate what we can express or what we think, the patterns of language do force us to focus on different things in different languages. These patterns mean that speakers of Guugu Timithirr have a much better sense of direction that English speakers -- not because their language makes it impossible for them to think in egocentric directional terms, but because their language requires that they identify position based on cardinal directions. The book also includes a section about gender in language, which, while providing some interested data, is in my view little more than a good way to introduce the idea that how we speak can influence how we think about things. The last part of the book wraps up with a good (and at least for me, eye-opening) summary of the evolution of color vision, which is certainly relevant to the points brought up in the book.
TL;DR: I hesitate to recommend this book just because of my own violent allergy to any suggestion that languages are not equal. Languages are of course very different, but I think any suggestion of inequality will only enforce in the minds of many the idea that "primitive people speak primitive languages". I am not swayed by the author's assertion that because languages differ in the complexity of their phonology, morphology, and syntax, this means that it is a mortal sin to claim that languages are equally complex. That being said, I found the other sections of this book not only readable but eminently informative and interesting. There is much to be learned here, both about the history of research into color terms and analysis of cross-linguistic color terms themselves.