The Russian psychologist Lev Vygotsky, formulating his theories of child development, described a stage of children internalizing conversations with those around them — social speech — into a conversation in their own heads. He called it “inner speech” and thought it enabled children to use language to reflect on and consider their own behavior. We continue that monologue with ourselves as we age into adults. It’s not quite the way we’d talk to those around us, though, with its cropped syntax and a “note-form” shorthand that represents your familiarity with your own thoughts. But it’s just like what we’re saying to our dogs — as if they were in our heads.
Snippet from NY Times article by Dr. Alexandra Horowitz: https://www.nytimes.com/2019/08/02/opinion/sunday/talking-dog.html
