Lunch that day was significantly more glamorous at 5 Hertford Street, London's latest fashionable watering hole, and came courtesy of Ben Goldsmith, the youngest of Jimmy's three children.
While brother Zac busies himself as an MP, and sister Jemima engages in a series of causes of variable worthiness, Ben has backed an investment company WHEB.
Given we already have thousands of investment funds and hundreds of investment companies we arguably don't need any more, but this has the merit of being distinctively different. Whereas most fund managers' philosophies remain substantially unchanged by the turmoil of recent years, WHEB is founded on the belief that we are in the early stages of a profound shift in the way industrial societies are organised and operate.
It believes the gradual spread of progressive environmental practices and technologies will open up new areas of profitable investment. Its management team is dedicated to understanding what is going on, and investing its money accordingly, and making money out of supporting others who are doing good.
The WHEB team are quite clear that they are investment managers and stop thankfully short of making any claim to be angels in bankers' clothing. But nevertheless theirs is an interesting proposition. The public have minimal trust in financial organisations. Will they be more inclined to believe in a firm which is committed to sustainability and where the money is devoted to meeting some of the world's most urgent challenges?
I suspect they will.