THE SHIP OF FOOLS - Hieronymous Bosch, 1500

No doubt the contemporary influence behind this painting was Sebastian Brant's satirical poem The Ship of Fools (1494).

But it may be (or, may not be!) that both Brant and Bosch had some awareness of the ship analogy in Republic Bk 6, which may with considerable justice also be called a ship of fools.

Admittedly, the Plato-Bosch connection is speculative (suggested by one George Gregory)!

More on the painting.