By David K. Johnson, Ph.D., King’s College
Questions of personal identity have always puzzled philosophers, and many have come up with explanations that could point the way to identifying what makes identity. So how about psychological continuity? Will the preservation of your complete psychological make-up preserve you, and is that what constitutes identity?

The ‘R Relation’ Between Psychological States
Think about your psychological state at this moment—what you’re believing, experiencing, remembering, etc. Now consider your psychology at this, the next moment. They’re remarkably similar, right? And aspects of the first directly led to aspects of the second.
Our adjacent mental states are related in this way. Philosopher Derek Parfit called this the “R Relation” or “relation R,” and considered whether the preservation of that relation between our mental states over time could be responsible for preserving personal identity.
Now, there is not an immediate relationship between your current psychological state and one when you were 8 years old. But there is a chain of related psychological states, each one related to the last, that traces back from your current self to your 8-year-old self. And, by this theory, it is in virtue of that, that you are the same person over time. But Parfit didn’t actually endorse this view. Why? Because it’s subject to many fatal objections. Let’s consider two.
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Sam Bell in Moon
First, psychological continuity can’t be what preserves identity because psychological continuity can be duplicated while identity can’t. Although, obviously, the same person can be in different places at different times, the same person cannot be in different places at the same time. Yet such things could happen if psychological continuity preserves identity.

Consider the movie Moon, in which a facility on the Moon harvests a future fuel source called Helium-3. The facility only needs one human to maintain and operate it. The movie opens with Sam Bell, the facility’s operator, who is almost at the end of his 3-year contract.
But this Sam is actually a clone of the original Sam Bell, and there’s an entire cache of Sam Bell clones underneath the station. Each clone lasts about three years, at which time he enters a pod which he’s told will take him back to Earth, but instead, he is incinerated.
The facility’s AI, GERTY, programs a new clone with Sam’s psychology and memories, and this clone awakens fresh and ready for three years of service.
This is a transcript from the video series Sci-Phi: Science Fiction as Philosophy. Watch it now, on Wondrium.
Continuity but not Identity
Sam 5 discovers he is a clone after he’s in an accident and left for dead. GERTY wakes a sixth clone who then overhears GERTY talking about an accident and decides to investigate. After Sam 6 finds Sam 5, they argue about which is the clone of the other, until they find out that they are both clones, and the original Sam Bell is actually living with his family back on Earth.
This premise stands as an objection to the psychological continuity theory. Sam Bell cannot both be: living at home on Earth with his family; and also, on the Moon harvesting Helium-3. Logically, these things cannot be true of the same person at the same time. And none of the clones can be said to be the same person, since they are in various states of death and life at the same point.
The Idea of Dollhouse
There’s a second objection to this theory: loss of psychological continuity does not seem to cause a person to cease to exist. Consider Joss Whedon’s TV show Dollhouse, which is about a secret organization that runs what is called a dollhouse in the film. Dolls are individuals who have had their entire psychology (memories and personality) erased. Upon request, the company can have a new psychology written onto them, thus making them “whoever you need.”

People volunteer to become dolls in exchange for having any problem in their life resolved, with the promise that they will get their personality back after 5 years of service. And Echo, the show’s protagonist, was apparently a person named Caroline before she volunteered to be a doll.
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Breaking Continuity, Persisting Identity
But we don’t think Caroline died when her psychology was wiped. She may have lost her sense of identity, but Caroline still exists. It’s Caroline who acquires the personality of a negotiator. It’s Caroline we feel sorry for when she exists as a mere blank between jobs.
And we don’t think Wendy (another doll) becomes Caroline when she has Caroline’s stored personality imprinted on her. In fact, we all hope that Caroline will get her personality back one day. In short, breaking psychological continuity does not cause Caroline to cease to exist, so psychological continuity must not be what preserves her personal identity.
Thus, we can see from the way identity is explored in Sci-fi, that psychological continuity can exist without identity, as in Moon, and that identity can persist, even without psychological continuity, as shown in Dollhouse.
Common Questions about Psychological Continuity and Personal Identity
In the film Moon, the protagonist Sam Bell is revealed to be one of a series of clones of the original Sam Bell. Each clone has the psychology of the original Sam Bell, but obviously they are not all the same person—the original Sam Bell is living peacefully on Earth with his family, while his clones operate for 3 years on the Moon before being incinerated and replaced by the next one.
The series Dollhouse has as its premise a technology that allows people to have their entire psychology erased—their memories, their personality, everything. People volunteer to become dolls in exchange for having any problem in their life resolved, with the promise that they will get their personality back after 5 years of service.
The protagonist of Dollhouse is a person named Caroline before she volunteered to be a doll. But we don’t think Caroline died when her psychology was wiped. She may have lost her sense of identity, but Caroline still exists. Breaking psychological continuity does not cause Caroline to cease to exist, so psychological continuity must not be what preserves her personal identity.