Primer is a 2004 American science fiction film about the discovery of a means of time travel. The principal characters are two engineers who accidentally create a device which allows an object or person to travel backward in time. The pair is ultimately unable to resist the temptation of using their machine to meddle with nearly every aspect of their own lives. This in turn creates increasingly complex problems which begin to dismantle their relationship with each other as well as with their sense of self.
Primerexamines the philosophical issues of chaos theory and how inventions can’t be divorced from human frailties, both mental and physical. It attempts to deal with the paradoxes of time travel: what happens when there are two (or more) conflicting versions of the future?
Furthermore, that within the same period of time there are different versions of the same person, Primer also raises disturbing questions about the metaphysics of identity. What does it mean if there is an infinite number of each of the characters, all facing a universe slightly different? Simplicity and common sense may rebel against such principles but serious versions of such metaphysics have been produced to deal with quantum mechanics and multiple real universes have been proposed by David Lewis to explain possibility and necessity.
At its heart, Primer also serves to ask ethical questions about the implications of scientific innovation: the power that such innovation can yield; the manipulation of events and the manufacture of changing causal patterns; and perhaps most importantly, the effects that each of these elements has on interpersonal relationships. As the director Scott Carruth points out, he intended the central theme of the film to be the dynamics of the relationship between the two protagonists, and specifically their inability morally to cope with the newfound power afforded them by their technological advancement:
“First thing, I saw these guys as scientifically accomplished but ethically, morons. They never had any reasons before to have ethical questions. So when they’re hit with this device they’re blindsided by it. The first thing they do is make money with it. They’re not talking about the ethics of altering your former self.”