The Greek philosopher Diogenes of Sinope (c. 400–325 BCE) occupies the centre of the composition. He holds his drinking bowl in his hand as he turns to an assembly of men, showing them a boy bending down at a stream to drink out of his hands.

Living like a dog
Being a so-called cynic (”kynikos”: Greek for “doglike”), Diogenes lived “like a dog”, i.e. with no material goods. The drinking cup was one of his few remaining possessions, and now, inspired by the boy’s example, he sees how that too is superfluous and casts it aside.

Important virtues
Salvator Rosa considered himself a painter-philosopher and was greatly interested in the neo-stoic ideas about ethics and moral philosophy current at the time, focusing on virtues such as endurance, constancy and restraint.