I have a mental model of my bedroom that no one else in the world has. No one has as intimate knowledge of what my room looks like or what’s in it apart from my wife. This is a personal mental model that I’ve developed for myself. I have other personal mental models for my purpose in life, my life story, my relationship with my cat, and on and on.
But many, perhaps even most, of my mental models are those largely shared with others: my notions of the legal system, money, and human rights and my belief that the world is round. These are all concepts or beliefs that human cultures have developed collectively and agreed to live by together. I didn’t create them. They were given to me and billions of others as a child or through various media.