The Ship of Theseus
You’ve likely heard of the ship of Theseus paradox, but to make sure we are all talking about the same thing… here is a quick overview: the ship of Theseus is a philosophical thought experiment about identity which asks whether an object remains the same if all of its component parts are replaced over time. If not, then at what point does it cease to be the ship of Theseus?
Is it still the ship of Theseus so long as fewer than 50% of its parts are replaced? Does it suddenly change when it breaches the 50% mark? If we think it changes long before this, is it still the ship of Theseus if we exchange only one plank on the ship? Or in the other extreme, is it still the ship of Theseus after exchanging every part of the ship?
And then, after every part had been exchanged, if all of the original parts were gathered together and reassembled, which ship would be the ship of Theseus?
Ultimately, it seems the question is: at what point does the ship of Theseus cease to be the ship of Theseus, and become something new?
And it seems many people have differing ideas of identity, and that identity itself is a complexity we cannot understand. Since we can hardly make sense of or agree upon a definite identity for the ship of Theseus—how could we come to understand or nail down the identity of living beings as complex as humans, or even societies?
But perhaps there is another answer we can discern by asking a simple question: why do people have different opinions on what makes the ship of Theseus’s identity change or not as parts are exchanged over time?
Google’s AI response, which is most likely fed through ChatGPT, tells us: “the paradox forces us to consider what makes an object or person the same over time, with no single definition being universally agreed upon. Some believe identity is tied to the continuity of its material parts, while others argue it’s defined by its continuous history, purpose, or a combination of these factors. Ultimately, the differing opinions stem from different philosophical perspectives on whether identity is a matter of physical substance, function, history, or a combination of all three.”
If you found this answer unsatisfying, then perhaps you sense or intuitively know there is more to it than Google AI’s response can grasp. I consider Google’s answer misleading. It assumes that people have different definitions for identity and that we cannot come to agreement on them, an assumption I would challenge, but I do find its answer partially helpful.
So what is going on with the ship of Theseus paradox?
Our understandings lie in context, and everyone answering the question of the ship of Theseus is filling in blanks by making assumptions about the context. Perhaps the assumptions they make are based on their personal experience, culture, or whatever other influences, but they are still assumptions made, yet we seem deeply unaware of our assumptions, and of others’ assumptions, so become stumped by this seeming paradox.
What is the object that ship of Theseus refers to? Is it…
A) Theseus’s ship?
B) The ship that Theseus is in command of?
C) Historical piece (the material components of the ship)?
D) Theseus himself, and his crew, aboard any ship?
E) The spirit of Theseus and his crew, like a code that men live by, that lives on even after their deaths?
We cannot agree on the “identity” of the ship of Theseus because we have not established the context in which the phrase is being used, so we can’t know what object is being referenced. If I reference ice cream by using the word chair, and don’t express this is what I’m doing, then of course we will disagree about what a chair is. The point being, before we can communicate anything of value, we need to clearly express the object we are referencing with a word. Often, this gap is filled easy enough with context, we all use ice cream to reference, well, ice cream, so we are operating on a shared understanding, or shared context.
If you are interested in seeing this in action, below is a series of statements giving brief context for the ship of Theseus. See if you can determine which object is being referenced in each of the examples below. The answers are at the end of this article. I’ve also created polls (scroll down) to track people’s answers over time.
1) “Did you hear the museum recovered the ship of Theseus, and it will be on display later this month?”
2) “As we head into battle, remember you are part of history already. The ship of Theseus lives on through us and through our actions; fight bravely and honorably, for we will be remembered long after this battle, as we remember and honor our forebears.”
3) “Apparently everyone who owns a ship has been asked to donate it to the navy. The ship of Theseus looks the best of the lot from what I’ve seen.”
4) “The ship of Theseus is the best trained and deadliest there is, even if their ship is sunk, they still manage to win the battle.”
5) “I’ve been assigned to the ship of Theseus. I’ve heard Theseus drives the men hard, but he’s a fair captain.”
Surely there are even more objects that the ship of Theseus could be referencing given different context, but the point is not to illustrate them all. The point is that if most people can discern the object being referenced, given context, then is there still widespread disagreement over what the ship of Theseus represents, and over what its identity is? Or is it simply that we make different assumptions given a lack of context?
Our earliest questions when first exploring the ship of Theseus paradox seem to only apply to object C, and whatever museum is housing the ship of Theseus display is likely to have a footnote addressing the question, stating what we see is just a model of what we think it looks like, or was a rebuild with as many original pieces as could be salvaged. If we still think this question is worth pondering, given the new context it exists in, then we can, but the reality for object C is that it is whatever you can convince people it is. A museum will want to call it the ship of Theseus to increase attendance, and tourists will want to call it the ship of Theseus to take part in history and feel like they are really experiencing it, so for object C, where on the spectrum of exactness the ship of Theseus’s identity exists is practically irrelevant. What seems more important is whether those initial questions ever had a chance of arriving at anything true, or only of entrenching people into their assumptions, thus blinding people to them. Did those questions serve to help us discover truth, or did they serve to cause confusion?
What are the implications of this understanding of the ship of Theseus? Can we say that, given the same context, or assumptions, man’s reason always leads him to the same place? So in disagreement, there is not an inability of one party to reason or a fault in a man’s reasoning, but a question of what assumptions or context is being used, and what we disagree about is what context is most accurate or true to reality?
What do you think?
Answers:
1) C
2) E
3) A
4) D
5) B