Eyes.

Upon reading "The Sandman" by Hoffman, what I noticed most were eyes. The author emphasized the use of eyes and sight to show themes of deception; "how the eyes can deceive," and "what's real and what isn't." For instance, Hoffman uses "automatons" in this story when it comes to the woman in Nathanael's life. I find it interesting that Thanael first accuses his lover of being an automaton because she thinks he is deceiving himself into believing in Coppelius, then after he falls in love with a real automaton, which Professor Spalanzini is trying to hide in normal society. Since an automaton is just a doll, the professor's attempts to hide her in society was scandalous, and brought about more fear of deception. The automaton, Olympia, also played a part in Thanael's deception. Thanael, who trusted his sight through a spyglass, and formed a "love" with Olympia through their eyes. So were his eyes deceiving him, or were her eyes deceiving her, or was Coppola's spyglass the culprit? I also thought it was interesting that Thanael initially thought the spyglass had "such clarity and distinctness." His trust in the wares of the person he thought was the eye thief Coppelius is astounding. There was also a point where Klara, Thanael's lover, tells him that his childhood nightmare could have all been childhood fancy, at which point we can question who is right and who is wrong? What role does each character play in Thanael's deception and madness?
In the end, Thanael's deception of himself or Coppelius' guidance of Thanael led to his demise.
We cannot be sure whether Coppelius killed Thanael or not because everything is not concrete. Even though Coppelius laughed and said "Ha, ha! Just wait; he'll come down on his own.," we cannot assume that Coppelius knew he would compel Thanael to jump, but rather, we can think that Coppelius assumed after Thanael's ravings, he would climb down himself, naturally. Is Coppelius really the culprit?