Where does old age begin? Don’t worry – I won’t be asking questions. It’s sort of rhetorical. I’ve been wondering but without really reaching a conclusion.

My father defined old age as anything beyond 40. Until he was 40. Then it was anything beyond 50 and so on. I remember as a child being decidedly unsettled by his frequent protestations that life beyond 40 wasn’t worth living and that, immediately upon attaining that landmark, he planned to put a revolver to his head. I honestly believed him. Mother reassured me – “he doesn’t have a gun”, which although mildly comforting was not really the point.

He regarded every tiny failure as a portent of impending intellectual apocalypse. He had only to fluff one clue in the Telegraph crossword to turn from genial parent into glum fatalistic octogenarian. Each tiny erosion of his cognition had the same effect. One minute he was reeling off Henry VIII’s wives, the next he was staring gloomily into his morning tea. It didn’t take much. A single momentary slip over a deceased aunt’s maiden name and he was immediately loading his imaginary revolver. And he was still only in his 30s.

Of course, with Parkinson’s, you get to fast forward a little. You can skip read some of Shakespeare’s normal stages and go straight from moderate self contented good health to stumbling hunchback in less than the time it takes to finish an average test match. Or so it seems.

The most obvious barometer of my old age is the perception of my children. They have, almost imperceptibly, gone from talking to me to talking about me. I exaggerate to make a point but the difference is clear if mercifully infrequent still. “Are you okay?” has gradually become “is dad okay?” I don’t think they even notice and they certainly don’t mean it unkindly. Indeed I think the opposite is true. I think it is a measure of their affection that they confer amongst themselves how best to help me.

This has practical implications of course. They no longer allow me to climb ladders, to clear gutters or to paint underneath the eaves. They make the point, firmly but gently, that I am no longer a fully fit 30-year-old (actually I don’t think I ever was) and that the consequences of any fall from height are likely to involve broken bones and a severe outbreak of Itoldyouso. At the very least. And worst case scenarios for hospitalised Parkies are… Well, let’s not go there. Suffice it to say that you can cancel the papers. So ladders are out.

So too, it transpires, are power tools. You name it and I’m not supposed to use it. Jigsaws, angle grinders, power drills, staple guns and so on. There seems to be a blanket ban. Even the leaf blower is questionable. I ask you, how much damage can anybody do to themselves with the leaf blower? At least I now know to keep stumm about the chainsaw in the toolshed.

So what is my point? Well mainly it’s this – that Parkinson’s somehow ramps up the perceived speedometer of infirmity. That people judge you as older than you are. I am 60, soon to be 61 (and happy to share my birthday list with you incidentally). I am weaker than I was, of course, but not yet ready to put away my power tools even if it does mean my children cowering behind the curtains waiting for the sound of arterial blood splashing on the patio, or holding their breath in anticipation of the next accidental amputation.

Of course old age is really just that little bit beyond your actual age. My father made it to 85. He never did find that gun.

A ripe old age