How do languages change?
Ojas Patil suggested long ago that I write a post about causes of language change. I had forgotten it until E, who’s already given me post fodder once via a comment on a Linguistrix post, asked me a follow-up question on my reply to his comment-question. It was heartening to see that E appeared reasonably convinced by my answers to his first question, and his question is quite interesting—
So how does language or grammar evolve (Because it certainly _does_ evolve)?