Theseus’ ship: at time X, the craft is fashioned of wood, cloth and metal. Its journey spans oceans, across trading routes, re-routed by the winds of economic flux; it survives pirates and wars. It gets pretty beaten up, weather worn, and is repaired along the way. Sails are mended, then replaced entirely; its hull refashioned from fir to pine; its ribs revamped from pine to cedar. It is repainted from green to gold. Eventually, at some time Y, nothing of the original ship’s material remains.
If one were to compare two photographs of the ship at X and Y, one would say they are different. Yet at any one point in its journey from X to Y, this cannot be said not to be Theseus’ ship. When one sail is patched, between time X.n and X.(n+1), it’s not a different ship, it’s just a minor repair. When its hull gets fixed at time X.(n+2), it’s just an improvement to the same ship at X.(n+1).
The paradox of Theseus’ ship: between each incremental repair, the vessel maintains its identity. Yet, ignoring this continuity, ship X and ship Y are different.
But we still consider them the same Theseus’ ship.
What property of the ship constitutes its identity? It cannot be its material. Not one atom of X remains within the body of Y. Therefore identity is invariant over matter. The atoms of the ship are unimportant to its sameness: there’s something else that makes it the same over time.
If Theseus’ brother were to purchase a copy of the ship, a simulacrum precise to the minutest detail, and stand it side by side with the original — we’d say they are not identical — one is a copy of the other, because they are clearly materially distinct. There is no lineage or traceability of identity from one ship to the other. They were created separately and, while similar, are not the same because the one ship did not, so to speak, evolve from the other. The simulacra are not like Theseus’ ships X and Y, where Y is traceable from X: we have a continuous trace, a temporal record of each step-by-step change to its life.
So it must be temporal continuity of material change to the original that must be inherent to the property of identity.
The Star Trek teletransporter thought experiment. In the distant future, humans develop a technology to transport ourselves from one point in space (point X, say Melbourne, Australia) to another point (point Y, say Mars) at the speed of computer network transmission. The technology works by means of two stations. At X, one station digitises the makeup of a person’s body to the smallest atomic detail, up to and including a snapshot of their brain and each electrical impulse running through its neutrons. The body is then painlessly vaporised. The data snapshot of the person’s body and mind is transported at the speed of light to be recreated, atom by atom, by a station at point Y.
Captain Will Riker departs at point X with some random thought about work and what to buy for dinner, his pain in his left side. He is teletransported to Y with the same thoughts, the same pain, the same body. It feels to Riker as though he has not travelled at all, but now he sees red sands of Mars through the window, as opposed to the coffee shops of Melbourne. Riker at Y feels himself to be himself, he has no doubt as to his identity in his thoughts. Of course he believes he is the same Riker who just stepped into the station at X: he remembers standing there a moment before and in the the blink of an eye he now stands here, with no experiential disruption to his sense of being. The only difference between Riker at X and Y is in a difference of atoms.
Is Riker X identical to Riker Y? Is Y deceived in his belief that he is the same as X? Is X dead and Y merely a copy? But if we are to follow through with our conclusion above, matter does not constitute identity. The fact they are made of different atoms is not a problem to their sameness.
If identity is understood as the temporal continuity of material change to an original, then Riker Y must be the same person as Riker X. There was no discontinuity: the teletransportation was as seamless a physical transformation for the person as stepping into a bath and washing off dead cells. Even less of a mental discontinuity than falling asleep and waking up, as their thoughts, their very neural activity remained continuous from departure from X and reinstantiation at Y. Awakening from slumber, we emerge with different thoughts, our selfhood has transformed more significantly than entering the teletransporter. So X and Y must be identical.
But what if the transporter malfunctions. Upon digitising at X, the Riker’s body is not painlessly vaporised, it remains at point X. The digital copy is sent to station Y and Rikers’s body and mind are recreated as before. Now there are two William Rikers. Each one believes in its identity, in material continuity with the Riker at the moment of digitisation. When they meet up, each would assert that they are the “real” Will Riker while the other is a mere copy.
Do we say Riker X is “more” identical than Riker Y, because his matter remains the same? Well then, matter must be inherent to identity. But the paradox of Theseus showed us matter is irrelevant to identity. And anyway, Riker Y would beg to differ — what gives you the right to say he is a mere simulacrum just because his atoms are different from those of X. Some were changed in a nanosecond at X, biology dictates. In 5 years’ time, Riker X will naturally age and his cells will regenerate and his atoms will be entirely different from now, just like Theseus’ boat. But Riker X in 5 years will still assert the continuity of his identity as Riker.
So what does this bifurcation mean? Perhaps it means that, in extreme cases, identity is not singular: that continuity is all that counts, and in some situations we can have two identical Rikers. Or maybe it means … And so the metaphysicians speculate …
Richard Rorty, one of the sole bridges between Ango-American metaphysics and modern Continental philosophy, would take an almost Buddhist or yogic or psychedelic perspective. That these thought experiments are physical extrema that present a metaphysical breaking point of identity. Like nirvana, or an acid trip, or a Shivasana, they present to us an indisputable dissolution of ego. Riker 1 looks upon Riker 2 and realises his ego is an illusion: they are not the same, they are not identifiable, because identity itself was an attachment, an illusion or mara of the world.
Wittgenstein in contrast (note my “in contrast”) would assert that the speculation above is an absurd waste of time, typical redundant metaphysics.
The philosophical question “What is identity” is meaningless as the term is not considered within a given language game, context, utility. We can talk about identity in practical situations like identical twins in biology, or identical cars in car salesmanship, or identifying yourself as a person for the purposes of your tax claim. Language is a human tool, just like a sword or a hammer or a machine: it is designed to serve functions of utility. The term “identity” is not meaningful, without a usage or functional purpose. The two thought experiments above are typically of metaphysical philosophy’s abuse of language — to take a term out of a useful, functional context and create a “paradox” when there is none.
Theseus’ ship has identity inasmuch as, say, it is useful for people to identify his ownership of the ship (a taxman, dock hands, sailors, Theseus’ himself) over time. Riker’s “identity” is meaningful inasmuch as “identity” is something useful for him/his linguistic community to manage (his taxman, his girlfriend, etc). If there are now two Riker’s, it means nothing to talk about which one is “really” him, or what “identity” is metaphysically — identity will only be useful as a concept when restricted to the two Rikers’ decision as to who gets a new tax number, who needs to take a new job, and which of them his girlfriend wants to continue a relationship with. These are particular decisions that hinge on the term that are useful and make the term useful. But these decisions, and usage of the term, are in no way dependent on the answer to some broader metaphysical question of “what is identity” — that question is meaningless as it does not have a usage-context to quality it.
Wittgenstein and the Buddhist Rorty seem to arrive at the same conclusion: “identity” is an illusion. But Wittgenstein’s logic is more complicated and epistemic — the Buddhist perspective remains metaphysical, albeit nihilistic and reductionist, to the extent that it confronts the primacy of Wittgensteinian epistemics: the thought experiment shows that, not only is Riker’s philosophical, spiritual sense of selfhood is an illusion, but it also intimates his sense of continuous being in other, pragmatic/utilitarian contexts, is equally deception. “Riker” as a taxpayer, “Riker” as a lover: all attachments to a concept that has no meaning in face of the Real, attachments to a momentary flicker of a concept, rendered smoke and mirrors within the magic of the thought experiment.
There is the metaphysical perspective, including its Rortian extreme, then there is the Wittgensteinian epistemic argument. All valid, but their ontological and epistemic primacy exists at the expense of a third suppressed term in the trinity of the philosophy of identity: drama. It’s like the Father of Metaphysics and Son of Reductionist ultilarian epistemology ganging up against the Holy Ghost of human emotion. Which is not surprising as the tomes of philosophy are written by rather INTJ type personalities. Yeah, I admit it, guys just like me. But I’ve learned a bit about emotion, so hear me out.
The thought experiments have an emotional impact on the reader. Read through the thought experiments above and revisit keywords: Riker feels the same, his girlfriend will have to choose between X and Y, intimating one Riker will dramatically dispute with the other as to who is authentic and who is the simulacrum. When we are confronted with Theseus’ ship or the Teletransporter narrative, we react emotionally to scenarios. “If it were my body in place of the ship, or my mind in place of Riker’s, how would I feel?”. Am “I” real, really real, or am I an illusion, just Adorno’s simulacrum to simulacrum to simulacrum, like some bloody Warhol iteration? Every stoned philosophy major has gone through this after their first year’s metaphysics 101 class.
Let’s not discount the emotional response to these thought experiments. Or the rest of them: what is Descartes’ meditations if not an extreme thought experiment that brings into question the existence of the entire universe, apart from ego. These things are designed to freak us out, to employ a hippie/raver venaculure. “Do I even exist?” “Do others even exist or do I imagine them?”
This is my point: Theseus’ ship is a threat to being, viewed not as a philosophical possibility, but as drama. It is not merely a meditation upon material continuity, but an act of philosophy as theatre whose objective is to displace emotionally our handle on selfhood. The teletransporter example, similarly: the imaginary mechanics of the teletransporter technology is a dramatic threat to us-as-Riker. We are rooting for Riker, but he inevitably loses, classical tragedy style like an Oedipus. I don’t mean he loses to the fate of ego dissolution. Rather, his emotional, narrative plight is suppression to the Mother of Cartesian Metaphysics, to the Father of Wittgensteinian Epistmology. Philosophy pretends it is not a text that makes people feel and react: fictional characters like Riker or Descartes’ ego, or real animals like you and me. But without this reaction, without this empathy response, philosophy would not exist.
Philosophy is a trinity of ontology, epistmology and drama. Since the dawn of time. You just didn’t realise it. Philosophy’s purpose is not to determine what individuality is, but to determine if you are an individual, within the ontological/epistemic/emotive nexus-narrative of your ego drama.
These thought experiments constitute an empathy test: like a strange loop, from philosophy into fiction, from fiction into philosophy, the ironic threat of the simulacrum to the identity of the self fictionalizing the self-as-fiction. Or maybe the self-as-fiction fictionalizing the self’s conflict with identity. Maybe both at the same time.