The Lighthouse is a masterful modern-day Greek tragedy from writer/director Robert Eggers. Substituting William Dafoe for Proteus (the godly knowledge-keeper) and Robert Pattinson for Prometheus (the Titan punished for stealing fire from the gods), this black-and-white thriller sucks you into the madness of the human condition—and does so through a well-balanced and capable narrative structure.
Gaslighting is a Psychological conflict bred from manipulation and co-dependency. Chasing after your brother like a homicidal ax-wielding maniac is a Physical conflict borne from gross misinterpretations and survival instincts. This balance of conflict finds a home in an Objective Story Domain of Psychology and a Relationship Story Domain of Physics.
The two remaining Domains—Universe and Mind—divide evenly between Thomas Wake (Dafoe) and Ephraim Winslow (Pattinson). Wake, as the Protean sea god, provides the influence of one having treasured knowledge. Ephraim, like the Promethean Titan, allows us to share in the visceral experience of one jealous of that position—envious enough to do whatever it takes to steal mythical "fire" from the Gods. This juxtaposition of an Influence Character Domain of Universe against a Main Character Domain of Mind, alongside the previous Domains, completes the model of the Storymind.
Ephraim's jealousy stems from a guilty conscience. Suspecting that he could have done more to save his previous foreman's life, Winslow (really, Thomas Howard) forms his new position into one of self-imposed exile—punishment for his past sins. Driven by this Main Character Problem of Order, Howard perceives this hellhole as justice for his crimes (Main Character Focus of Equity. He self-flagellates himself as a matter of recourse (Main Character Direction of Inequity).
Wake, on the other hand, finds himself driven by an Influence Character Problem of Inertia. The old man, like all gods, cares only for maintaining his position over those who look up to him. Confronted with the reality of his shortcomings (an Influence Character Focus of Actuality), the supreme being engages in deception and falsification (an Influence Character Response of Perception).
Match Wake's Focus and Direction of Actuality and Perception with Howard's Problem of Order, and you strike a recipe for disaster through gaslighting. Internally, Howard's drive is to maintain his mental construct; externally, Wake provides psychological release through the construct of master and servant. That dual drive of Order allows Wake to shift what is happening (Actuality) into a moment of doubt as to what appears to be happening (Perception).
The Lighthouse is a cautionary tale turned into a whole story. Tales warn; stories argue. The crucial narrative Element of Chaos ties both subjective and objective points-of-view into a thought-provoking Premise generated from Subtext:
Everyone suffers the tragic consequences of understanding what it means to exist, when you get out of your way and manifest bedlam.
Is this not the purpose of the Promethean myth? Is it not argued to the fullest and proven to be valid within the context of The Lighthouse?