As I wandered back home in the early Sunday evening following a lazy hour spent in the garden of the village pub, I passed several people walking dogs and a few children playing on bikes before I stumbled upon a frail old lady on a mobility scooter, walking her elderly dog.

I say “walking” – the scooter was barely moving over the uneven ground which led through the woods, and I was unsure whether it was the dog which was taking its owner for a gentle exercise or the other way round. It was certainly unclear who was taking the lead.stool

My initial reaction was one of surprise at the slightly incongruous sight, but only a few minutes later my mind had distilled out a few of the critical dependencies which appeared to be involved in that little excursion. Continue reading