The concept of privacy itself is notoriously difficult to define. In reading around the subject, I found this description of it by Larry Peterman in a 1993 essay in The Review of Politics titled ‘Privacy’s Background’:
We look upon the private as that part of our lives insulated against the communal or public broadly constructed, protected from unwarranted intrusion by others, including political authorities, and the place where, in the last resort, we can clothe ourselves in anonymity.
I think that is exactly right. It is what Grant Mindle, in an earlier essay, calls ‘concealment and seclusion’ that protected place where we can have parts of our lives that will not leak into the public arena.