The teenager who offers me her seat is pretty, I notice. Am I still allowed to notice that? With the warmest of smiles, she rises and steps into the aisle with courtesy bordering on a curtsey. I am wrong-footed, then conflicted. “No,” I scream silently, stifling an internal laugh, “I come from a generation where I do that for you.” I realise immediately what a strange and bygone place that is.

Speech fails me; I burn with embarrassment and confusion. Later, I reflect that this is an act of unfettered kindness, an example of the goodness of a maligned generation. I bow in recognition, but feel bowed with shame. I am fit, able, strong. In my head, I am young; she shocks me by making me so acutely aware of my advancing years.

To accept the seat is to accept that new status – elderly, needy, requiring care – a status I am not yet ready to embrace. To decline is to snub an act of generosity. To prevaricate is to appear ungrateful and , ungraciously dithery. To explain, on a crowded bus, is impossible.

This dilemma is played out before the other passengers, whose inquisitiveness is that of doleful, cud-chewing cattle. What if, once I am seated, an older person boards and no one gives up their seat? Do I remain motionless and burn with shame, or stand and relinquish my newly received gift – a slap in the face for the kindly girl?

I manoeuvre awkwardly into the seat, smile and sink my head on to my chest, in childlike submission to a world that has consigned me to a new role. The bus stumbles to a halt. I shuffle down the aisle and out into the rain, a Rubicon crossed.

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