One time, when I was in my early twenties, I drove down to the south of France with my then girlfriend. We were both members of the International Marxist Group and engaged in "revolutionary tourism" - we were going to stay with comrades in Montpelier. At some point in the journey, under blazing summer skies, the car broke down. It was her car, not mine, and I had neglected at any stage to check the oil so it had all burned off. Somehow, in a strange village and in halting French I have the faintest trace of memory that we got the car fixed and I received a dressing-down from the mechanic for my stupidity.
As I reflect now, my memories of that day extend no further. I have no idea how I went about solving the problem - I can't inhabit that scene at all: the 'me' of forty years ago might as well be a complete stranger. (An unkind person might say that at least practical cluelessness is an historical invariant).