If Black English Isn't A Language, What is?

What exactly amounts to language? The author James Baldwin, an African-American writer has a very reasonable stand on what language is all about. Being part of the Civil Rights Movement and having lived in other parts of the world, where languages can have a far more divisive instead of unifying role he gives a very logical argument about language. “Language, incontestably, reveals the speaker” is his key aspect around which he has structured his argument.
His example about France and the French language, spoken in various parts of the globe, logically supports his argument of people being defined by and defining a language. In this example he breaks language down in its many parts, such as control, means of confronting life, political instrument and as a “crucial key to identity”. With that, he points out that language can be a uniting or divorcing force among the people who seem to speak this language. When he says language reveals private identity, I totally have to agree with him, since it feels like I am in the exact situation day-in and day-out. I cannot open my mouth and speak English WITHOUT people recognizing that I am not a native speaker. Like Baldwin puts it, I confess my parents, my youth and my social background right away.
Additionally, he describes Black English as a language separately from White English being developed during the earlier American history of slavery. In his mind Black English is to be seen as a monoculture existing apart from White English which was being out of the WHITE ignorance.
After all, he argues his point very consistently avoiding logical fallacies and providing the reader with lots of descriptive examples to support his claim.