“Diogenes was knee deep in a stream washing vegetables. Coming up to him, Plato said, “My good Diogenes, if you knew how to pay court to kings, you wouldn’t have to wash vegetables.” “And,” replied Diogenes, “If you knew how to wash vegetables, you wouldn’t have to pay court to kings.””

— Diogenes Laërtius, Lives and Opinions of Eminent Philosophers

The equation for the energy balance of a leaf! @solarpunk