In my preachin’ days, I used to remind congregants that, if they wanted to know what really was important in their lives, they should ignore those religious creeds they recited by rote, and instead look at their MasterCard statements. In those columns of black and red lie a large part of the story of our lives — decisions about bottles of wine, trips abroad, music, books, theatre … yes, even pets. Our chequebooks (together with our calendars) write a digital autobiography — things we’ve chosen to do, meals we’ve chosen to eat, friends we’ve travelled to see, and so on.

And here’s the thing. Every one of those choices has an ethical component. In the column you reference, I made the point (which, strangely, some found controversial) that we live in a world of aching human need. The World Health Organization estimates that 1.5 million deaths among young children are due to diseases preventable by routine vaccination. As many as five kids can be immunized for a dollar — that’s a hundred kids who might live, for the price of the wine I drank at dinner tonight. That takes some of the fizz out of popping a cork.

I’m not arguing we should live ascetic lives, wracked by guilt every time we see a movie. My own MasterCard statement speaks too loudly for that. I am, however, arguing that, whenever we spend a dollar, we have an obligation, at the minimum, to weigh the implications of that expenditure on the environment, our community, and our world.

Gandhi, among many other truth-speakers, taught us to live simply, so that others might simply live.