To unlock The Bright Minds trophy in Assassin's Creed Odyssey, you simply need to complete the game's fourth episode.
Assassin's Creed Odyssey Episode 4 Quests:
- Memories Awoken
- Welcome to Athens
- A Venomous Encounter
- Escape from Athens
- Ostracized
- Perikles's Symposium
- Drink Up
- Oil and Love