I had a perfect example of this when visiting my mother recently. We both lived in the same house when I was growing up. The same circumstances, the same environment, the same family members. What she remembers and what I remember are two different worlds. I listened to stories and wondered, 'Were we in the same place when this happened?', even when I knew we were.

And when you have witnesses to an accident, it is common for every witness to have a different account of what happened.