It depends on what you mean by the change being done 'instantaneously'. Since such a thing is impossible, it is hard to imagine what you have in mind.

Consider instead a process involving millions of very skilled tiny workers who, working together, could replace every plank or other component so quickly that the entire replacement takes place within a millisecond. Then I think we can argue that the final product is the same ship, as long as only one plank at a time was replaced (say taking a picosecond per plank).

On the other hand if the ship were exploded by a bomb and another built in its place, with all new materials, I would say the new one is not the same ship, regardless of whether it took a millisecond or a year to build.

So maybe I'm agreeing with you that time is not the important element. It seems to me that what is important is that only one component at a time is replaced - so that the ship is not missing say more than 1% of its components at any instant.

My thinking on this is guided by a process metaphysics, a la Whitehead, which I find a very satisfying and paradox-free way of looking at things.

So maybe I'm agreeing with you that time is not the important element. It seems to me that what is important is that only one component at a time is replaced - so that the ship is not missing say more than 1% of its components at any instant. — andrewk

Thanks for seeing my POV. I may be wrong but your condition that ''the ship is not missing say more than 1% of its components at any instant'' makes no sense without a time factor in it. And time, as you and I agree is irrelevant.

When I say that 'time is not the important element', I mean the time it takes for the change process to be completed. We can't disregard the time dimension competely, because that would make it impossible to even refer to 'the ship afterwards' and 'the ship before'

Which of the two ships (A or B or both) is the ship of Theseus? — TheMadFool

They're both instances of the same particular; they're effectively duplicated, or cloned. The referent is only important insofar as you need to direct people to board or load or sail the appropriate vessel - 'you, get on B. You, you're to get on board A. '

'A is going to Thessalonika, B is going to Crete.'

I don't see any paradox here.

When I say that 'time is not the important element', I mean the time it takes for the change process to be completed. We can't disregard the time dimension competely, because that would make it impossible to even refer to 'the ship afterwards' and 'the ship before' — andrewk

I'm sorry I didn't express myself as well as required. I do understand that we can't just throw out the entire notion of time.

So maybe I'm agreeing with you that time is not the important element. It seems to me that what is important is that only one component at a time is replaced - so that the ship is not missing say more than 1% of its components at any instant. — andrewk

You posted the above and if you'll notice your paragraph ends with the words ''at any instance'' and this, if I understand you, reintroduces the temporal element as in the speed of destruction/construction of the ships A and B.

You seem to be saying that the ratio of old planks to new planks is relevant (

not missing say more than 1% of its components...

). But this relevance is tied to the notion of speed (time) of construction/destruction which you agreed is irrelevant.

No one doubts that A is a referent of ''the ship of Theseus. — TheMadFool

But you have two very distinct descriptions of A. You have the original ship, and you have a later ship which is built out of salvaged materials. The original ship is clearly "the ship of Theseus", because you have bestowed this identity upon it in your description. Later, you have built another ship out of salvaged lumber. Why would you give this ship the same name as the other ship? That makes no sense unless you are doing this intentionally to create ambiguity. This, other ship, which is built from salvaged material is what you should call ship B.

Furthermore, there is no "ship B" as per your description. Ship A can go through as many changes and repairs as you want, and we still identify it as ship A. To change its name to ship B because it has been repaired X number of times, is unnecessary and unwarranted. Identity is maintained through a continuity of existence, so ship A does not become ship B just from going through numerous repairs.

To explain, imagine if ship A was torn down at one go while simultaneously replacing the parts to build ship B. Permit me to use the word ''instantaneous'' here. So, if the whole exercise was done instantaneously there would be no doubt that A is the ship of Theseus. Ship B is just a copy of A.

Therefore, the gradual replacement of ship A's parts counts as a relevant factor in the paradox. But is it truly relevant? — TheMadFool

You should respect the fact, that to completely destroy something is to annihilate it, and deny the continuity of its existence and therefore identity. To rebuild a copy, is as you say, to rebuild a copy. But this is different from your original description which has ship A being repaired, and its continuity of existence maintained, and its identity maintained.

'A is going to Thessalonika, B is going to Crete.'

I don't see any paradox here. — Wayfarer

But which one does ''the ship of Theseus'' refer to? A or B

Imagine a person A. Over the course of time his entire being is replaced at the atomic level. Would you not say that person A is, despite the dramatic change in his constitution, still the same person A we began with? Isn't ship B the ship of Theseus?

Continuing from there, we collect ALL the atoms that were replaced in person A and reconstitute it as another body in its original configuration. Wouldn't you say this is person A? Isn't ship A the ship of Theseus?

So which ship A or B is the the ship of Theseus?

This is the pardox.

I like the following answer in a poem by Steve Gehrke

The Ships of Theseus

The answer of course is that the ship
doesn’t exist, that “ship”
is an abstraction, a conception,
an imaginary tarp thrown
across the garden of the real.
The answer is that the cheap
peasantry of things toils all day
in the kingdom of  language,
every ship like a casket
of words: bulkhead, transom,
mast steps. The answer
is to wake again to the banality
of things, to wade toward
the light inside the plasma
of ideas. But each plank
is woven from your mother’s
hair. The blade of each oar
contains the shadow of
a horse. The answer
is that the self is the glue between
the boards, the cartilage
that holds a world together,
that self is the wax in
the stenographer’s ears,
that there is nothing the mind
won’t sacrifice, each item
another goat tossed into
the lava of our needs.
The answer is that this is just
another poem about divorce,
about untombing the mattress
from the sofa, your body
laid out on the bones of the
double-jointed frame, about
separation, rebuilding, about
your daughter’s missing
teeth. Each time you visit
now you find her partially
replaced, more sturdily
jointed, the weathered joists
of   her childhood being stripped
away. New voice. New hair.
The answer is to stand there
redrawing the constellation
of   the word daughter in
your brain while she tries
to understand exactly who
you are, and breathes out
girl after girl into the entry-
way, a fog of   strangers that
almost evaporates when
you say each other’s
names. Almost, but not quite.
Let it be enough. Already,
a third ship moves
quietly toward you in the night.

... about your daughter’s missing teeth?

Please check my response to Wayfarer

Continuing from there, we collect ALL the atoms that were replaced in person A and reconstitute it as another body in its original configuration. Wouldn't you say this is person A? Isn't ship A the ship of Theseus? — TheMadFool

No, as I explained, I don't agree. Why would you think that completely annihilating an object, and then completely rebuilding a copy of the original object, with the same parts, constitutes having the same object?

This "paradox" simply illustrates how identity is not an intrinsic aspect of macro-scale objects; it is something that we assign to them in accordance with our purposes. Strictly speaking, ship A at one time and place is not identical to ship A at another time and place, even if none of its planks have been replaced yet. Instantaneously replacing all of its planks just makes it more obvious that it is a different object.

So ship A becomes ship B, but remains "the ship of Theseus" because people continue to call it that, despite the replacement of all its planks. As @apokrisis would say, echoing Bateson, for most people having one new plank - or a lot of new planks, or even all new planks if they are replaced gradually - is not a difference that makes a difference for the purpose of referring to the ship. Hence I suspect that most people would call the reconstructed ship A something like "the original ship of Theseus" to distinguish it from ship B as "the current ship of Theseus."

The played out metaphor is between personal identity and the ship's identity. Ships are traditionally female.

No, as I explained, I don't agree. Why would you think that completely annihilating an object, and then completely rebuilding a copy of the original object, with the same parts, constitutes having the same object? — Metaphysician Undercover

Let us imagine a scenario which hopefully will make you see my POV.

Ship A needs to be transported from city x to city y. However, it has to be done by land and also it becomes necessary to disassemble it for easier transport. These kind of situations are quite common. So nothing difficult in imagining it.

After the parts of ship A reach city y they are reassembled in the original exact configuration. In this case annihilation is present but the ship A hasn't lost its identity. There is nothing grossly wrong in holding such a belief.

So ship A becomes ship B, but remains "the ship of Theseus" because people continue to call it that, despite the replacement of all its planks. As apokrisis would say, echoing Bateson, for most people having one new plank - or a lot of new planks, or even all new planks if they are replaced gradually - is not a difference that makes a difference for the purpose of referring to the ship. — aletheist

Yep. It is the purpose, the finality, that causes the ship to be repaired and so there is unbroken continuity in the identity - for all practical purposes, as they say.

And even if the boat was replaced in toto instantly - as in Parfitt's Star Trek transporter: https://en.m.wikipedia.org/wiki/Teletransportation_paradox - then still the intent is what perseveres through time and maintains identity.

If the transporter works by dissolving your molecules at one end and then - via a transmission of information completely specifying your form - recreates you at the other, then your identity is preserved.

But note now that the logical requirement is your body at the departure point must be destroyed. There are problems if the goal of transporting you leaves this earlier you still stuck at the other end - or now this dopplegager replicant at the arrival end.

So make the change instant and the erasure becomes as important as the replacing. And so really even with a slow change of the parts, the rotten planks of the ship should be burnt to secure the identity of the new.

If we ask ourselves, "what makes that telescope that particular telescope?", we have already assumed that there are such things as telescopes. We already have presumed it right to believe objects in general exist.

But what would make an object? What composes or constitutes an object?

I think it is fairly common to see artefacts, or human-made stuff, isn't really "anything" outside of what we see them as. A hammer is only a hammer to the eyes of the wielder.

But what about modern inventions, like genetic engineering or artificial intelligence? If there's no ontological difference between a solution of hydrochloric acid in the lab and hydrochloric acid in a digestive tract, then what is the difference between a cow born naturally and a cow cloned in a test tube?

And the fact is that humans are not separate from the rest of the world. The world produced humans. The phenomenon of human creativity is not something spawned from the endless depths of some ethereal dualistic plane of existence, but a phenomenon that is rooted right in the world as a whole. The world produces agency.

So we can ask a further question: what difference does it make if objects exist or not? Would it make any real difference in the grand labyrinthine causal structure of the universe if a telescope actually existed, or if it were simply a structure of simples organized telescope-wise?

Neither theories seem adequate in my opinion. There is too much ambiguity and vagueness in nature to be able to set any real strict boundaries between material objects. But there are patterns the universe falls into, patterns which the mind is able to pick up. And here we have the threat of extreme nominalism: maybe all the "work" is done by the mind, maybe it's "all in the mind". But we simply have to put this into the perspective of a cosmology and evolution, and question how or why something like a mind would arise out of a mess of non-patterns and disunity.

So the verdict, in my view, is that the reality of objects is determined by their causal role in a system, which includes minds. What we call something is irrelevant, the fact is that something materializes as a real entity as soon as it becomes an active part of a causal system, and dissolves or mutates into something else as soon as it loses or switches roles. This includes things that signify or represent something else: a piece of clothing may not "actually" be a piece of clothing, but it is something that tells me I can wear it for warmth and to avoid indecent exposure. It's not an "object", but it's not "nothing" either. What something is is not simply a question of its material constitution but of its relationship to other things as well.

What something is is not simply a question of its material constitution but of its relationship to other things as well. — darthbarracuda

This is a very important point. Identity is only possible within a context, where we can distinguish one "thing" from all of the other "things" that are reacting with it in its environment. As I said before, we do so in accordance with our purposes. Sometimes an object's material constitution is what matters most to us, but not always - maybe not even often. As you said, its relationships with other things - including, and especially, ourselves - likely matter more in most cases.

This "paradox" simply illustrates how identity is not an intrinsic aspect of macro-scale objects; it is something that we assign to them in accordance with our purposes. — aletheist

Agree.

Imagine a person A. Over the course of time his entire being is replaced at the atomic level. Would you not say that person A is, despite the dramatic change in his constitution, still the same person A we began with? Isn't ship B the ship of Theseus? — TheMadFool

That is a bit of a 'bait and switch' I'm afraid. Persons are not objects, but subjects of experience.

What something is is not simply a question of its material constitution but of its relationship to other things as well. — darthbarracuda

This is a very important point. — aletheist

This is a very important point indeed. While trying to find out ways of explaining "top-down causation" to some friends of mine, this has come close to becoming my philosophical motto.

When this point is not sufficiently attended to, then the relation of material constitution becomes liable to be confused with numerical identity. But something can persist through time as the thing it is (and remain the same individual) while gaining and/or losing material parts. So, material constitution isn't identity. The statue isn't (or need not be) the lump of bronze that it is made of since it can be destroyed while, at the same time, the lump of bronze persists. Likewise, a ship isn't (or need not be) the set of planks that make it up -- even with the qualification that the planks remain suitably arranged so as to preserve its function -- since the ship can persist through the replacement of some (or even all) of its planks.

Those considerations, though, only partially solve the paradox of the ship of Theseus. I owe the fuller illumination of this problem to Peter Simons (Parts: A Study in Ontology, OUP 1995/2000) and David Wiggins (Sameness and Substance Renewed, Cambridge University Press, 2001)

The trouble with the standard telling of the story of the ship of Theseus is that, while it makes explicit the issue of the relationship of "the ship" with its parts, it obscures the fact that there are actually two different contenders for being the object singled out as "the ship" (since "ship" signifies two different sortal concepts with incompatible persistence and identification criteria associated to them, as explained below); and both of them metaphysically relate to their parts in different ways thus pulling our intuitions regarding the persistence and identity conditions of this (ambiguously named) object in two different directions.

There is first the historical artifact -- some sort of a relic -- that we may think of as "the ship of Theseus" and which is such that we do care very much about its retaining at least some -- and maybe most -- of its original constituents. Else, at some point in time, it ceased to be what it was qua historical artifact (or relic). The same is true of most works of arts, such as a Picasso painting say, where we do care that the canvas, or paint, not be replaced even as the form might be maintained.

And then, secondly, there is the functional artifact -- the seafaring vessel -- that retains its identity through carrying forward its function (through maintenance and repair, etc.) This object is not the same thing that we previously named "the ship of Theseus", though nothing prevents us from giving it the same name, just as two different men can be called "Peter". The crucial thing is that, whatever name we give "it", the "it" that is at issue very much depends on the way "it" (and the sets of its material parts) not only hang together, functionally, but the way in which "it" (and the relevant function) relates to our pragmatic interests. Since nothing stands in the way of our having simultaneous pragmatic interests in singling out more than one object -- e.g. an historical artifact and a functional artifact -- then, it may occur that the original "ship of Theseus" (as singled out at the moment of its historical origin -- had material constituents that make up two different objects that merely happen to occupy the same space and share the same material constituants at that point in time but are liable to have divergent histories, spatial trajectories and material constituants some time in the future.

At the end of the story, there is one historical artifact that is identical to the original "ship of Theseus" (the historical artifact that essentially originally belonged to Theseus) and another, different, functional artifact that is identical to the original functional artifact that we also want to name, misleadingly, "the ship of Theseus". This is the functional seafaring vessel that, as it happens, originally but non-essentially belonged to Theseus. Just as is the case for the statue of Hermes and the lump of bronze that materially constitute it at a time, those two "ships" (qua historical artifact and qua functional artifact) are two different objects.

(This accounts rests on David Wiggins's thesis of the sortal dependence of identity, whereas the account earlier suggested by Wayfarer relies on the thesis of relative identity, defended by Peter Geach. I think Wiggins's account accomplished what Geach's account seeks to achieve while eliminating its severe logical problems)

The Ship of Theseus is the one its crew have been using all along as it gradually became replaced. You could not build a working ship out of the old parts which had presumably been replaced due to becoming individually defective. If they had been individually defective, then what kind of a ship could be built out putting them all back together? The fucking useless Ship of Theseus, perhaps?

If they had been individually defective, then what kind of a ship could be built out putting them all back together? The fucking useless Ship of Theseus, perhaps? — John

You can imagine a variation of the story where the planks have been replaced for merely cosmetic reasons and the paradox remains.

I don't see a paradox, even in that case. In that case the unused ship rebuilt out of unattractive parts would be the fucking ugly Ship of Theseus. Even if it were used by a different crew it still wold not be called 'the Ship of Theseus'. If it replaced the Ship of Theseus then it would be the replica built out of old ugly parts that became the new Ship of Theseus for some stupid reason.

I don't see a paradox, even in that case. In that case the unused ship rebuilt out of unattractive parts would be the fucking ugly Ship of Theseus. Even if it were used by a different crew it still wold not be called 'the Ship of Theseus'. If it replaced the Ship of Theseus then it would be the replica built out of old ugly parts that became the new Ship of Theseus for some stupid reason. — John

You seem to be arguing that, in a case where some artifact is being disassembled and later reassembled, then what determines the identity of the reassembled artifact with the original is the beauty or ugliness of the reassembled object, or the wisdom or stupidity of the motivation for assembling it. What if there were an wise and intelligent motivation for reassembling a ship from its original parts, and the reassembled item would be even prettier than the continuously repaired ship?

What other reason can you think of for the parts of a ship being replaced over time other than their dysfunctionality or lack of aesthetic appeal?

The Ship of Theseus in any case would be the one that had been used by Theseus' crew and thus deemed to be that entity. Another ship that had been rebuilt out of the old rejected (for whatever reason) parts could not be called the Ship of Theseus, unless it replaced the original, and even then it would really be the Ship of Theseus 2, (even it were called 'the Ship of Theseus') because it is could obviously not be the same ship.

Let us imagine a scenario which hopefully will make you see my POV.

Ship A needs to be transported from city x to city y. However, it has to be done by land and also it becomes necessary to disassemble it for easier transport. These kind of situations are quite common. So nothing difficult in imagining it.

After the parts of ship A reach city y they are reassembled in the original exact configuration. In this case annihilation is present but the ship A hasn't lost its identity. There is nothing grossly wrong in holding such a belief. — TheMadFool

It all depends on how you describe the act of dismantling and assembling. If this is described as a continuity of existence of the object, then it becomes part of the object's identity, as per the description. That is the case in your example. If the act is described as an annihilation, and the rebuilding of a new object, then there is no such continuity of existence, as per the description. There is a description of one object ceasing to exist, and a new one coming into existence. So for instance, if you break a drinking glass, and collect the pieces, melt and remold them into a drinking glass, we would describe this as one object being annihilated and a new one coming to be.

The point is, that identity, as a continuity of existence is something which is assumed. Continuity of existence has never been proven, so you hear things like people wondering if an object continues to exist if it is not being looked at. Since continuity of existence, and therefore the "identity" which is associated with it, is just an assumption, then what constitutes continuity of existence, in our beliefs, depends on how we define it.

What other reason can you think of for the parts of a ship being replaced over time other than their dysfunctionality or lack of aesthetic appeal? — John

The reason why someone might collect the discarded parts might be because she sees the process through which a ships is being continuously maintained and repaired through substitution of material parts to amount, in this specific case, to a progressive destruction of a historically significant artifact and she hopes to, some day, be in possession of all the original parts and to be able to reconstitute the original. Your insistence that this is not possible because the continuously maintained functional artifact *is* (and remains) *the* original "ship of Theseus" is begging the question against her.

No, a ship reconstructed from discarded parts could never qualify as the original for two reasons; firstly because it would not replicate the physical condition the ship had been in at any point in its history, and secondly because those discarded parts had ceased to be part of the ship, and had remained so for varying periods, and had thus not participated in its entire history.

It's true that replacement parts did not participate in the entire history of the ship either but current parts had become part of the ship and remained so until the time when any substitution might be proposed.

The identity of the ship does not reside in any part, but in the whole structure, with its entire historical trajectory and facticity.

No, a ship reconstructed from discarded parts could never qualify as the original for two reasons; firstly because it would not replicate the physical condition the ship had been in at any point in its history, and secondly because those discarded parts had ceased to be part of the ship, and had remained so for varying periods, and had thus not participated in its entire history. — John

It could actually come even closer to replicating the physical condition the ship originally had been in than the continuously maintained ship does. Your second objection, if valid, would entail that a fully disassembled object could never be reassembled as the same object it originally was. Disassembling a piece of furniture for purpose of shipping, for instance, would amount to irreversibly destroying it, on your view.

It's true that replacement parts did not participate in the entire history of the ship either but current parts had become part of the ship and remained so until the time when any substitution might be proposed.

This doesn't explain why, on your view, some objects can't still persist in disassembled states, or, at least, couldn't be brought back into "active" existence as (numerically) the same objects that they originally were before disassembly. What if you are chopping some wood and the head of the axe flies off the handle. After you've glued the two parts back together, is it necessarily a new axe that you have now manufactured, on your view? Why might this not count as your having repaired the old axe?

The identity of the ship does not reside in any part, but in the whole structure, with its entire historical trajectory and facticity.

Yes, I agree with this but I would go eve further and -- following darthbarracuda -- I would potentially include the ship's external relationship to *other* things (including ourselves, our pragmatic interests, and our conceptual skills) as part of the determination of the objects identity though time (or as part of the transcendental constitution of the object's form, to put it in a Kantian/Aristotelian way).

There is first the historical artifact -- some sort of a relic -- that we may think of as "the ship of Theseus" and which is such that we do care very much about its retaining at least some -- and maybe most -- of its original constituents. — Pierre-Normand

That would be the ship with all its "accidents". So to get the metaphysics right, it has to be sortal (or constraints-based) in Peircean type fashion. Our notion of identity has to include the accidental or contingent in smooth natural fashion too.

So that is where the causal notion of purpose pays off. A purpose - in its potential for satisfaction - also spells the further possibility of indifference. After a while, the details cease to matter because the general purpose is being served (and aught else then makes a real difference).

Thus it can be accidental that one of the ship's planks is made of kauri rather than oak. The different woods achieve the same purpose from the ship's point of view. And therefore it continues to make no difference if the ship eventually becomes all kauri, returns to all oak, or gets made of some other wood of equivalent sea-going, ship-making, qualities.

So it is possible always to get fussed about preserving the accidents of history. From the ship's point of view (ie: in terms of the formal and final causality that are the people who designed something for their own purpose), the actual wood is a matter of indifference - if it serves its purpose. All further difference gets classed categorically with the accidental. And yet there is still (say the metaphysically obsessive) another point of view ... the god's eye or transcendental view of history where all accidents are fixed in the memory of existence and never forgotten or erased. So beyond particular purposes (like wanting a ship to cross the sea) there is going to be a metaphysical level generality in which even accidents are essential to notions of identity.

But you can see the trap inherent in claiming accidents as essences. The nominalist path that leads to the Society for the Preservation of Historical Accidents really doesn't want to make claims about the reality of essences. Yet in trying to skirt the existence of differences that don't make a difference, nominalists in fact double down on essentialism without realising it.

So a Peircean style triadic approach can smoothly handle this little problem with the accidental as a component of the purposeful. Pragmaticism says that everything starts in pure contingency or accident. and then limitations arise to suppress most of it. So sortal concepts or constraints cannot eliminate the accidental - that must always be present as history gets fixed. However constraints can limit the accidental aspects of identity to the degree that it matters in terms of some global essence or sense of purpose. So continuity can be defined in that way, regardless of the continuing presence of innumerable localised accidents - the differences that don't make a difference, like whether a ship's plank is oak, kauri or teak.

And then, secondly, there is the functional artifact -- the seafaring vessel -- that retains its identity through carrying forward its function (through maintenance and repair, etc.) — Pierre-Normand

Yep. It is the telos or function that is the source and determiner of continuity. That is what would have to be extinguished.

This accounts rests on David Wiggins's thesis of the sortal dependence of identity, whereas the account earlier suggested by Wayfarer relies on the thesis of relative identity, defended by Peter Geach. — Pierre-Normand

So I have defended an equivalence between sortal concepts and constraints. But then also they speak to quite different metaphysical orientations as well.

Constraints make it clear how they operate - as the limits on freedoms. Thus they rely on proper holism. Whereas sortal concepts are the product of predicate logic - the reasoning from the particular. It rather avoids the central issue to simply point out - in circular fashion - that having more than one of some thing suggests a further thing of which it is "a sort".

Circularity is bad. Hierarchy is good. Recursion needs to transcend scale to make sense. Hence you need an inherently reciprocal metaphysics in which to frame an understanding of identity - one in which the globally top-down and the locally bottom-up are each other's natural inverse.

It could come much closer to replicating the physical condition the ship originally been in than the continuously maintained ship does. — Pierre-Normand

A ship built out of entirely new parts would come closest to replicating the original condition of the ship (i.e. its condition when newly constructed, and prior to use). A ship built out of old worn out parts could not replicate the condition of the ship at any time in its history because it would not have consisted of all worn out parts at any time; so I'm not sure what you are trying to claim here.

Disassembling a piece of furniture for purpose of shipping, for instance, would amount to irreversibly destroying it, on your view. — Pierre-Normand

It seems to me that this argument is irrelevant because in the case of something being disassembled and then reassembled, its period of "non-wholeness" is part of its history, and cannot be considered a "destruction". (This has everything to do with human intentions). In any case, the case of the disassembled furniture is not at all analogous to the case of the ship that is gradually repaired, because the original functional ship continues to exist during the entire process, despite the fact that all its parts might be ultimately replaced, and stored somewhere, and later used to rebuild another ship.

I would potentially include the ship's external relationship to *other* things (including ourselves, our pragmatic interests, and our conceptual skills) as part of the determination of the objects identity though time (or as part of the transcendental constitution of the object's form, to put it in a Kantian/Aristotelian way). — Pierre-Normand

Well, I didn't read the whole thread, I just responded to the OP straight up. But I have already covered this aspect of identity by defining the Ship of Theseus as the ship which was used by Theseus and his crew from the beginning to the end of its history, and was designated as 'the Ship of Theseus' throughout the period of its history (although this latter is not guaranteed to be correct, as it is logically possible that another ship could have been substituted without any of those who designated it as 'the Ship of Theseus' knowing about it)..

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