How Do You Know When You're Nearsighted and Astigmatic?

I was really fascinated how you managed to recall the minute details of childhood so successfully. I just wondered whether this is something that you've always been able to do, or whether you had to do a lot of research into certain aspects of childhood and Canada at that time. Although cows and trees featured in my childhood landscapes, ants and shells and stones were much clearer to me. If you are nearsighted and astigmatic, you did say things up very close and very, very clearly. This wasn't discovered until I was 12, so I had a kind of foggy few years there. The Ruskin experience was that he was brought up by his mother and not allowed to have any toys.