I wanted to comment on the idea of eyes and glasses as a way to discern the truth in the movie. Leonard’s job as an insurance investigator required him to know if people were lying to him about their claims. He said that he had to look people in the eyes to know if they were telling the truth, and he continues to use this method after the accident and he cannot trust anyone. However, this method is unreliable, as is the “truth” that he ascertains from it, because whoever is talking to him only has to deceive him for a few minutes, until he cannot remember them anymore. Glasses also symbolize hiding the truth, as they block the eyes and prevent Leonard from looking the person in the eye. Natalie wears sunglasses when they meet in the restaurant and he has to ask her to take them off so he can know if she is being truthful or not. Teddy always wears glasses, and this aligns with Leonard’s note on the back of Teddy’s picture, not to believe his lies. However, the viewer sees the story unfolding from Leonard’s point of view and has the advantage of being able to remember what he is shown, but cannot know for sure if any information received from Teddy or Natalie is to be trusted. Natalie sums this up when she tells Leonard, “You can question everything—you can never know anything for sure.” This applies to the audience as well. We know the events that have happened, that Leonard killed both Teddy and Jimmy Grantz, and probably others as well, but we do not know for sure the true circumstances that led him to that point. “The world doesn’t just disappear when you close your eyes, does it,” Leonard asks at one point. But for him, it does, and not just when he closes his eyes, but after a certain amount of time, since he has to re-orient himself continually because of his condition.
The movie is definitely circular in its plot and series of events. It is also self-aware, as Teddy warned Leonard that a bad cop was setting him up and that bad cop turned out to be Teddy himself. He was warning Leonard about himself, but without revealing his identity until the climax of the film. Returning to the circular chain of action in the film, however, if Teddy was the one keeping Leonard going, with new John Gs to find so he has a reason to exist and thus not end up like Sammy Jenkins, what happens now that Teddy is dead? Leonard’s tattoo shows that the man he is after has the license plate that Teddy has, so without that leading to a new person, will he just go in circles, finding someone who no longer exists? Will he write himself a new note to tell himself his revenge mission is complete? If so, then is his destiny to become Sammy Jenkins, the fate he was trying so hard to avoid that he altered his own version of his memories?