The Old Man and the Knee

Although in his seventies, Christopher Matthew is convinced he is not yet old. No one one has ever stood up for him on a crowded bus or tube. He plays golf and walks the dog. He has all his own teeth, hair, and does not require a hearing aid. He is, in short, enjoying late middle age and is making the best of it while he still can.

'I know it can't last for ever, but while it does, it gives me the chance
to look at life in the last lane, as I am now experiencing it, and to consider what might be to come.'

Subjects range from what's the point of a grandparent; the perils and pleasures of replacing one's partner with a younger model; and acquiring new interests and hobbies (bridge? ocean cruising? ballet? marathon running?) to the arrival of old age and the last leg of all.

How do we know when we are old? Does old age creep up slowly or arrive out of the blue? Will we be able to summon up some half-decent last words and what should they be? Witty, like Oscar Wilde's about the wallpaper, or helpful like the 1st Lord Grimthorpe's 'We are low on marmalade'?