|The Tower of Babel by Bruegel the Elder|
The Power of Babel- A Natural History of Language
by John McWhorter
I can't get enough of linguistics because... I want to understand the rules that underlay speech and communication on a macro/global level. It's not the same thing as being interested in learning foreign languages or being interested in a specific foreign language. I was terrible at my junior high, high school Spanish classes, and I've never made any kind of effort to get back to it (even though I have a job where it would come in handy), nor have I tried to learn another language like French or German, even though I read plenty of literature in both languages.
McWhorter's main thesis is that every language is always changing, so that any thoughts/ideas about "proper" English or any other language is based entirely on the subjective beliefs of humans embedded within specific cultures and does not reflect any underlying truth, and people are not bad or ignorant because they speak a language that differs from the norm.
There are many current examples with which a casual reader will recognize. The two main ones in America are "Ebonics" or "Black English" and "Spanglish" or "Spanish-English." Much of The Power of Babel revolves around discussions of the difference between a Pidgin and a Creole- one being not quite a language and the other being a new language (created out of other pre-existing languages.) An equal or greater amount of time is spent discussing the important point that all languages, high, low or whatever are essentially "dialects" it just so happens that certain languages, for example, Standard English happen to be situated in a place and time where they ride to power and are then preserved by a combination of status and writing systems.
It's linguistics 101 that writing a language down has a conservative impact on the changes that will occur in every language written or orally. Thus, the standard English spoken today was the dialect spoken in and around the London area around the time the printing press was disseminated in England. McWhorter repeatedly points out that while we can basically understand Shakespearean English, Shakespeare himself would be unable to comprehend the language spoken as "English" in 1000 AD, as would we.
There is also the obligatory paean to all the vanishing languages of the world, though not without the observation that many "separate" languages in less developed part of the world are so similar that they are mutually intelligible and simply represent the ways smaller units of humans self identify. He also makes the observation that so called separate languages in the First world are more often the result of political/cultural considerations. A good example he gives is Danish/Swedish/Norwegian. The Danes used to control Sweden and Norway and Swedish was simply "Eastern Danish" and Norwegian was "Northern Danish." Then Sweden became independent and the people began to speak "Swedish" all of a sudden.
Ultimately, one should be interested in ways of speaking not because of what your English teacher tells you in school, but because speaking a language properly is a key to upward mobility. As a lawyer, it is perhaps useful for me to be as comfortable with Spanglish or Ebonics to facilitate communication with my clients, but they hire me so that I can speak to Judges and Prosecutors (and Jurors) in a way that will create succesful outcomes.