Final answer:
Odysseus leaves Circe's island to return to his home in Ithaca and to reunite with his family, demonstrating the central theme of nostos. His journey is marked by divine intervention and wisdom, showing his heroic determination.
Step-by-step explanation:
Odysseus leaves Circe's island due to his desire to return to his home in Ithaca and reunite with his beloved wife Penelope and son Telemachus. Despite the comforts and immortality offered on the enchantress Circe's island, his longing for home and family prevails. The decision to leave aligns with the central theme of nostos, the Greek word for homecoming, which is a dominant motif in Homer's epic.
In the broader context of the Odyssey, the protagonist's journey is fraught with trials, tests from the gods, and seductions that threaten to detour him. The sojourn on Circe's island serves as a significant turning point for Odysseus, reflecting his steadfast determination and intrinsic heroic qualities, such as resilience and wisdom. Additionally, the act of leaving is often guided by divine intervention, prophecies, or the counsel of others, including the seer Tiresias, who instructs him regarding the impending challenges on his voyage back to Ithaca.