Theseus' Ship: A Ghost in Time

The famous story that has puzzled many minds for thousands of years is the paradox of Theseus and his ship.  Critics fear it and great minds embrace it.  The story tells of young Theseus sailing home on a ship, after killing an evil Minotaur, and setting thirteen young Athenians free.  As the ship decays, each piece is replaced in order to preserve the original.  Eventually, there is not one piece of wood left that is from the original ship of Theseus.  In an attempt to save the original ship, a second boat is rebuilt using the pieces of the old and decayed wood.  The problem lies here – which ship is Theseus’? Though both boats are built to look identical, they do not behold the same identity.  Perhaps there lies a third boat.
         Heraclitus, a Greek philosopher, believed that nothing can assert identity for any amount of “time” at all since objects constantly undergo change.  This allows many uncertainties of whether anything is capable of persisting through “time”.  Heraclitus suggested the following, “On those who enter the same rivers, different waters flow.” This is to say that since the water undergoes constant change, that no person could ever step twice into the same river.  In relation to young Theseus, followers of Heraclitus would say that the original ship ceased to exist as soon as a new piece was fitted to the boat.
         When the Athenians realized no original pieces of Theseus’ boat remained, they rebuilt the ship using the original, decayed pieces. In order to retain identity, a sameness of parts is essential; however, the instant the Athenians tore down and rebuilt the ship using the original parts, they interfered with the ship’s existence and stimulated the flux doctrine. The flux doctrine explains that everything is constantly changing and therefore no object can retain all of its components or – pieces – from one moment and onto the next.  This is precisely what Heraclitus argued and, therefore, leads to the conclusion that in fact neither of the boats are the original belonging to Theseus.  Though both ships appear to be identical to Theseus’ ship, they merely represent an illusion.
         If neither ship is the original of Theseus, then there still remains an unexplained answer of where the original ship actually is.  To more effectively explain the whereabouts of his ship, one may picture this example: a human being is born into a state of pure originality; however, over maturation the cells in a growing body become replaced as the child evolves and changes into an adult.  A fully grown human no longer retains its original state as an infant – or to delve further, a single cell – and the child it once was is lost forever.  Since an object changes compositionally, it is impossible that Theseus’ ship was capable of persisting through “time”.
         This paradox in particular, along with all of its reasoning and debates, is somewhat misleading.  If the original ship is incapable of persisting through time, it is important to define what is meant by time.  Kant argued that time is a man-made construct associated with memories, events, numbers, predictions of the future, and even feelings.  It was St. Augustine who came to the realization that time does not exist, only the present instant does.  “A single hour contains minutes that vanish as they pass. Whatever minutes have passed no longer exist, and whatever still remain do not yet exist.”  This observation is very similar to the example of the constant flowing river.  The only difference is that time is a mental construct – all in the mind – and a river is a tangible entity.  How curious, yet frustrating, that the continual changes of an object do not lie only within the physical elements but also within the mental.  It is presumable then, that thoughts and ideas are capable of change because they are always in constant motion and reasoning, thus, if they never remain the same, perhaps there is not one original that exists, but nothing that exists at all.  If time can be measured, then surely each moment in time has a halfway point.  Upon discovering the halfway point, it is agreeable to state that it too has a halfway point and so on.  If this can be justified as correct, then it would suffice to say that logically, nothing moves at all.
This is the point where many frustrations occur.  It is quite ironic that problems should arise in this paradox as even reasoning allows itself to be contradicted – logically, nothing should move, yet each object undergoes continual change.  One philosopher to point out this problem was Irving Copi.  He noted that the problem with identity through time could be found by examining the following statements which appear true, yet not:
If a changing thing really changes, there can’t literally be one and the same thing before and after change;
However, if a changing thing literally remains one and the same thing, (i.e. keeps identity) throughout change, then it can not really have changed.
Therefore, nothing can be said both to be and not be something at the same time. This is the principle of consistency. If a statement is understood to be logical then it must be consistent.
Aristotle attempted to solve the problem of identity through time by introducing the concepts of “accidental” and “essential” changes.  Accidental changes do not result in a change in identity after the initial change.  These are thought to be changes that are accidental properties of an object.  For example, the Athenians replaced one piece of the original ship in order to preserve its existence.  Essential changes are changes which do not preserve the identity of the object when it changes.  An example of this is before the Athenians re-built the ship out of old wood, the pieces lay in an unkempt pile, resembling nothing of a ship.
Many have looked to spatio-temporal continuity upon explaining the problem of one object being in two places at once.  To explain more clearly, if an object exists at one time and again at a later time, then it exists throughout an interval.  For example, if half of Theseus’ ship is in a pile of scattered planks, and half of the ship is still in the form of a ship – new replacement pieces included – then it exists at one place at one time and a different place at a later time, therefore, tracing a path through space.  Since the ship changes each time a new piece is added, the ship continues to exist until it is a form that is utterly different, yet temporarily related to the second ship.
The problem in regards to Theseus’ ship does not lie within which of the two ships are in fact his; however, it poses a new question, “is the ship his at all?”  The possibilities of the original ship are limitless.  If one researches further back into the story, Theseus went to Athens in search of his father.  One day, a ship with black sails entered the harbour and the whole city became mournful.  This is the same ship Theseus embarked on to kill the Minotaur and it is the same ship he presumably returned home in.  Thus, one cannot say that the ship rightfully belongs to him solely because he sailed home on it. There were thirteen other members in accordance to the ship that should equally bear credit to the voyager.  Perhaps it would be better named as King Minos’ ship, or to the workers who built it.  Before it was named Theseus’ ship by the Athenians, it belonged to others.  Perhaps young Theseus did not wish for the ship to be in his name at all.  This possibility allows for the conclusion that identity is not only limited to an object, but of the self as well.  This ship was named after Theseus but he did not proclaim it so.  Thus, humans do not choose their own identities, but they are chosen for them by a society in which individuals adhere to.
The paradox has only ever alluded to two ships; however, such limitations allow only so much to wonder.  For example, suppose that during his voyage to the labyrinth, Theseus rebuilt the ship entirely.  When it harboured in Athens upon its return, the Athenians assumed it was the same ship; however, one can fathom the possibility of the original ship lost at sea.  Another possibility is – using the concept of the flux doctrine – if the ship remains the original as it endures harsh weather and bumps against rocks.  This ship constantly undergoes changes as the wood chips away from the planks.  No matter how small the chip is it is not the same ship anymore because in order to retain identity, completions of all parts are required.
To press the matter further back to the time of construction of the ship, one might ask if the moment the ship is finished, if it is purely original. Then again, what is a ship?  Locke said that ideas are representative of things themselves, thus, a ship is not a “real” thing but a collection of things working together to create a sense experience of a ship.  In the case of Theseus’ ship, it was made out of wood; therefore one may be led to believe that a purely original state of a ship lies within a tree because it acknowledges the possibility of the creation of a ship.  It is hard to distinguish when the ship becomes completely original, whether it is the idea of a ship, during the construction period, or the unveiling of the final product.  By asking these questions, one may gain a better understanding of the identity theory and the state of originality.
The mystery of this famous paradox does not end by asking which Theseus’ true ship is, but it entails a more important significance.  The Athenians were so overjoyed with the victorious return of Theseus that they wanted to keep his memory alive by preserving the ship in which he returned.  Over time, as the ship decayed, they replaced each piece to restore the ship.  They did not realize that by each piece they replaced, they were actually destroying the ship they loved in an ironic attempt to protect it.  In conclusion, the answer is that neither of the ships were ever actually those of Theseus’.  This is where the idea of the third ship evolved.  The third ship is not physical nor was it ever in the story, yet it is a metaphor linked to the concept of identity.  If nothing can retain identity for any time at all, since all objects remain in constant continual change, then here lies a problem: perhaps mankind’s idea of identity is merely the representative of a thing in which does not exist. The puzzle which has twisted and tortured great minds for thousands of years casts the realization that the all-powerful and unbreakable identity is that which is false; thus, a boat which does not exist.




Works Cited
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Gallois, Andrew. “Identity Over Time” 18 March 2005. 2 April 2009.
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