At Sāvatthī. “Mendicants, these four fuels maintain sentient beings that have been born and help those about to be born. What four? Edible food, whether solid or subtle; contact is the second, mental intention the third, and consciousness the fourth. These are the four fuels that maintain sentient beings that have been born and help those about to be born.

And how should you regard edible food? Suppose a couple who were husband and wife set out to cross a desert, taking limited supplies. They had an only child, dear and beloved. As the couple were crossing the desert their limited quantity of supplies would run out, and they’d still have the rest of the desert to cross. Then it would occur to that couple: ‘Our limited quantity of supplies has run out, and we still have the rest of the desert to cross. Why don’t we kill our only child, so dear and beloved, and prepare dried and spiced meat? Then we can make it across the desert by eating our child’s flesh. Let not all three perish.’ Then that couple would kill their only child, so dear and beloved, and prepare dried and spiced meat. They’d make it across the desert by eating their child’s flesh. And as they’d eat their child’s flesh, they’d beat their breasts and cry: ‘Where are you, our only child? Where are you, our only child?’