Nick Carraway is not a very trustworthy narrator as can be seen when Jordan calls him dishonest, yet we don't know exactly why. The green light is a symbol of something unattainable for Gatsby, yet it is also a symbol to go and meet Daisy. Whether or not he is Great is up for the reader to decide, some would say he's great for fighting his destiny, other would say he's a fraud who can't escape what he is no matter how hard he tries.
