I think I know why old people get grumpy

Apart from the aches and pains that increase with age, which obviously would make anyone grumpy. But Tim and I have noticed something in recent months – that things we thought that everyone knew aren't actually as obvious as we thought.

I mean, I'm used to the fact that not everyone knows the frequently strange and obscure things I have learned in my travels, and I'm never surprised when something even *I* think is odd knowledge isn't recognised. But there are some things which, for people of ...