On the train home from work today I picked up a copy of 'Ariel', the BBC's in-house magazine. John Nathan-Turner died last week, apparently. His was the name that appeared at very end of 'Doctor Who' when I was a child, and I have a vivid memory of his production credit hovering on the screen at the end of the programme. I'm not a great fan of the show and I know nothing of Nathan-Turner except that he is dead.

I don't know how many names I have seen scrolling by in the credits of television shows and films, but for most of them I can't place a face or a person. Who is Jim Finnerty, Key Grip on 'Platoon'? I have no idea, and as long as I don't know him, he will live forever, at least in my mind. Nathan-Turned died last week, but to me he didn't die until today.

I don't know what it's like to grow old - I'm only 26 - but I suspect that it will involve most of the people I grew up with, on television and in books, dying off. The Apollo astronauts, George Martin, Frank Oz, Rolf Harris, I'll wake up one morning to find a short obituary of them on Teletext. And then I won't be able to remember the past without remembering also that it's gone forever, and that the edge of the world is slowly creeping towards me.

I'm not a people person. I like machines and books, designs and ideas. They don't let you down, or grow infirm, they don't betray your trust, and they don't leave. A car might break down now and again, but only through poor maintenance or random misfortune; never maliciously or through spite or hatred.

The people I mention above, they're all ideas, at least as far as I am concerned. I didn't know Frankie Howerd or George Harrison as people, I knew them as faces and voices, I had an impression of a person. I had an idea of what they were like, and although the people are gone the idea remains, in my head, where it will remain until I too am gone and all my ideas are consigned to the eternity of post-mortal annihilation.