Mentalising and how the mind works

I don’t like the word but I find it an intriguing topic….We assume others understand the world like we do.But many  unfortunate people did not have the security of learning that we all have minds,thoughts etc and others do.Some of us can’t tell a thought in our minds from reality.Whether or not you can do this,it helps one to know some others cannot do it,So if they think something they believe it is real…I find the early development of the mind is fascinating just as is the early beginning of human cultural development,language skills and so on.I feel they are linked