Originally Posted by ShivaBlizzard8
Exactly. It's a temporal paradox, in which the effect happened before the cause. (the effect being Garden's creation, and the cause being Squall going back in time). That's what makes any story dealing with time travel so confusing; there's the whole matter of if Squall hadn't grown up yet to travel back and give Edea the idea, how could Garden exist? But then, the cause (Squall telling Edea) happened first regardless of how old Squall is now to witness the effect (the creation of Garden and his attendance).
To make a long story short:
1. Edea DID NOT come up with the idea for Garden. Her only idea for it came from Squall.
2. Since this event happened in the past, that's why Gardens exist regardless of whether Squall has traveled back yet.
3. Since the whole story is about Fate it makes sense; Ulty's fate is to repeat this cycle over and over, Seifer's fate is to follow her, Rinoa's fate is to become the next sorceress, and Squall's fate is to estab lish Garden to protect the world from sorceresses by giving Edea the idea in the past. :)