Why did Gatsby buy the house across the bay from Daisy?

1 Gatsby buys his mansion across the bay from Daisy as part of what Nick calls "the colossal vitality of his illusion." Gatsby wants to reunite with Daisy, and the mansion serves two purposes in achieving that goal.

2 The main reason Gatsby has the house on West Egg is so he can see this green light and feel closer to Daisy. The water between West Egg and East Egg, however, symbolically represents the social divide between Gatsby and Daisy that they can never bridge.