According to Peter Fonagy, “Mentalizing is the process by which we make sense of each other and ourselves, implicitly and explicitly, in terms of subjective states and mental processes. It is a profoundly social construct in the sense that we are attentive to the mental states of those we are with, physically or psychologically.”
In other words, when we mentalize, we recognize that our own perspectives and understandings are based on our own filters and meaning structures and are very different from those of any other person. When we try to understand another person’s experience, we take into account that his or her understanding will be specific to him or her.
While this may seem like an obvious concept, we do not often make the effort when we are with other people to stop and recognize that we are operating out of our own assumptions. But the important part of this idea is that it is the way that we connect deeply with other people: It is the basis of our feeling of closeness with another person.
One of the fundamental experiences of our lives is a wish to be seen–to exist in the mind of another person or persons. This is the antidote to loneliness and despair. And the way that we get this feeling is when we are deeply understood in ways that feel accurate to who we think we are. When another person can reflect to us that they see and understand us in the way we understand ourselves.