How many beans....?

Four here but I planted 23 in all: broad (fava) beans that will come up in the spring, flower and produce pods next summer.
This year's fallen oak leaves are sprinkled on the earth that I dug  over last week.

I've often wondered if the poet W.B.Yeats actually thought about how many beans  nine rows would provide for a single person living alone. I suppose that if he dried them they could carry on feeding him through the winter. But surely some greens would make his diet healthier?