If Superman were alive today, he'd be just another extremist moral relativist. There is a great deal of evidence that human memory is essentially reconstructive in nature.
Truth is perceived, rather than experienced directly.
The validity of truth depends on the accuracy of perception, relative to that which is perceived. I began life on trial, with my mother as judge and jury. We didn't share much truth, because a fundamental requirement for shared truth is a shared perception of reality. I know a little about her reality. Her life was being Mrs. Dr. Wilson.