“Disobedience, in the eyes of anyone who has read history, is man’s original virtue. It is through disobedience and rebellion that progress has been made.” – Oscar Wilde
Walter violated laws of the universe when he crossed over to save Peter. David Robert Jones crossed ethical lines with his real-world-as-a-laboratory experiments. Nina Sharp withheld information that could have helped the fringe division. Altlivia deceived everyone on our side.
But the character whose prohibited actions have had the most impact is September. He broke the rules when he visited Walternate in 1985 and distracted him from curing Peter. September’s interruption set off a string of events (and alternate events) that have unfolded over the past four years on Fringe. September’s initial interference led to continued disobedience of the Observers and ended in season four with him siding with the humans.
But he didn’t switch sides over night. Let’s take a look at September’s development.
The Observer: When we first meet September, he seems exactly like all the other Observers. He dresses like them and speaks like them. Most of the time, he stays in the background, simply watching.
The Interrupter: September wanted to witness the moment when Walternate cured Peter, but he accidentally distracted Walternate. When Walternate failed to cure Peter, September had to interfere to save Walter and Peter from drowning in Reiden Lake. Peter was safe, but he was in the wrong universe. Even worse, Walter’s crossing upset the balance between the universes. All because of September.
The Sympathizer: Again and again, September shows up to help Olivia, Walter, and Peter. September isn’t supposed to make contact with present-time humans, but he keeps disobeying the Observers’ rules. At the end of season two, September appears to Olivia and, as a warning, leaves her a picture of Peter activating the Machine. In season three, September prepares Walter to sacrifice Peter (so that later Peter can bridge the universes and heal both worlds). The bridge doesn’t completely erase Peter from the timeline, though, and instead of finishing the job, September’s lack of action allows Peter to re-enter the timeline. September cares what happens to Olivia, Walter, and Peter, so he warns them about future events, prepares them for what’s coming, and deflects the other Observers’ attempts to reset the timeline. Which finally leads us to…
The Rebel: At the end of season 4, September explains to Walter that the Observers are going to invade Earth in 2015. This is September’s final act of disobedience: warning the fringe team about the coming invasion and in doing so, giving them time to prepare a defense.
September’s disobedience puts him back in touch with emotions—the essence of being human. His rebellion allows for progress, but not in favor of the Observers. Instead, September’s actions allow him to help the fringe team. We don’t know the primary reason for September’s disobedience, but fan theories suggest that he is the young boy in “Inner Child” (season 1, episode 15). If that’s true, maybe September is returning the favor: the fringe team helped him, so he helps them. Perhaps we’ll have a definite answer in season 5.