If you really think your view of yourself in the mirror is totally realistic and objective, you need to read up on some psychology. NO ONE has an objective view of his/her self.
This is the big lie of both religion and psychology, perhaps influenced by religion. 'No one' is an absolute statement. I have known many people who have well integrated personalities with a realistic and objective view of themselves with or without the mirror. They know their strengths and their weaknesses but nothing is hidden from themselves. In fact, I find this to be the normal human condition for those not exposed to religion or psychology. Admittedly a small sample, but a sample that I try to spend most of my time with."