At the vegetable shop, the well-dressed woman bought two tomatoes and one lemon. Well, yes, it was fairly minimalist - but not startling enough, I would have thought, to drive the other customers into such a state.
"Was it worth her while coming out in the rain?" asked the woman with the basket of leeks and celery.
"Imagine what her social life must be like," said the other woman, who carried six oranges and four huge, flat mushrooms.
But, of course, you can't tell what anyone's life is like by what they buy. Thirty years ago I used to buy great boxes of condoms because I went to London a lot more often than friends. It did not mean the exciting and interesting social life it might have implied to the casual onlooker - or, indeed, to the Customs men, had I been caught.
There's a mild man who buys four giant bottles of disinfectant every week. The girl at the checkout told me he must have some unmerciful problems with drains and you'd want to cross the road passing his house - but in fact, he does voluntary work in a club for old people and takes on the responsibility of keeping the cloakrooms in good shape.
I have seen a couple drive back from a day Northern Ireland in a car filled to the roof with toilet paper. You might think they ran a hotel or had a slight incontinence problem but this is not so: they are compulsive savers and bargain hunters and it was 4p a roll cheaper in the North.
In Hollywood, scouts for the tabloid papers search the dustbins of celebrities for an indication of the life lived behind the walls and security cameras. It's very hard to know what they could discover that would give them a lead - after all, if people spend fortunes protecting their privacy they are unlikely to leave syringes, hard core pornography or empty poitin bottles in their garbage.
But the effort to find out about people's social lives from external evidence goes on - fairly uselessly, in my opinion. You can, in fact, draw any conclusion you like from what you see.
If a celebrity is seen walking thoughtfully by the sea, that could mean he is a simple, unpretentious family man with core values; or that he has had a row with his wife and had been thrown out of the house; or that he is planning his off-shore banking; or that he needs the exercise.
If you see a well-known person all dressed up at the theatre, you could say she likes to be seen in public; or that she loves plays and supports the theatre all the time; or that she is having an affair and the only way she can meet her lover in public is by going to functions like this.
It is almost impossible to know what anyone's social life is like unless you ask - and even then, you have to read the answers carefully. Because it's a slightly intrusive question to put in the first place. It's like wanting to know something about a pecking order in which you might get higher marks for giving dinner parties and going to symphony concerts, and lower marks for going to the pub or out for a pizza.
I asked a London couple who I don't know well what their social life was like, and to my amazement they seemed to think I was asking for an invitation somewhere. They rushed into an explanation of how simply dreadful they were and frightfully guilty about entertaining and had fallen desperately behind and must get something together in the New Year.
The whole concept of social life has come to mean something much more pressurised than just the hours between finishing work and going to bed. If social life is mentioned or questioned at all, people are inclined to bristle and become defensive and say there's a great deal to do and not enough time to do it in - as if there was an accusation that they might be sitting, friendless, night after night, looking at four walls. You really can't just ask questions any more out of pure interest because you are demanding that people define their dreams, and put too much about themselves on the line.
ONLY if you are doing an interview is it acceptable. I once asked an American woman novelist what her social life was like and she told me she and her husband were afraid of their housekeeper so they couldn't have anyone to dinner. Lunch in the garden was acceptable, but only just. They wore big fluffy slippers because of the carpets and the parquet floors; they ate their evening meal from a tray in a small room off the kitchen. They couldn't have a dog but they had a caged mynah bird in the garage.
I presumed she was sending me up and laughed good-naturedly to show I didn't mind being made a fool of. It turned out this was indeed their social life and she couldn't understand why I was laughing.
Perhaps it's too personal a question to ask. Ever.
Suppose someone asked you today what kind of a social life do you have, would some kind of shutters come up?
Would it make you look into your soul and analyse the situation so far? Like all those years ago when you were a child and some mad adult asked you what were your hobbies? Do you remember raking around trying to guess what might be the right answer?
I keep thinking of the woman with the two tomatoes and the one lemon and the inferences drawn . . . she was friendless, thrifty, on a diet and it would be no fun around her place. For all we may have known, the lemon was for enormous gin and tonics she was about to pour and the tomatoes to garnish huge salmon sandwiches.