Remember the passage of the Argonauts between Scylla and Charibdis?

Scylla would devour the crew alive by its dog heads, leaving the ship intact but drifting on its own - that's a metaphor of madness: for the crew is the mind, and the ship is the body;

Charybdis would suck both the crew and the ship into its whirlpool - that's a metaphor of death.

The goal is to pass in between.