the philosophical study of ontology in objects with different morphologies, but equal set of constituents
Will not be covering:
The reason for all this is to talk about the age-old Ship of Theseus paradox. I was thinking about it earlier and kept going down a rabbit hole in my mind.
The paradox can be solved with the axioms and definitions above.
Let's say that a particular object exists. A subject will provide the identity to the particular and call it The Ship of Theseus. It is up to the subject on why it was named what it was, but more importantly, what the identity means to the subject.
If I remove a single panel of it, then both the panel and the remaining ship are partial identities of the identity which is The Ship of Theseus. They are both parts of a whole. They have now become iterative subsets of the particular due to the dimensional changes/seperation of the panel and the remaining ship.
If I were to add another panel to the ship, then the object (combination of ship + new panel) becomes an iterative superset of the iterative subset (the ship without the old panel). The iterative subset is objectively a partial identity of The Ship of Thesesus, therefore this property is inherited in the iterative superset. The iterative superset's identity is up to interpretation by the subject, who deems it on the function of the object. Therefore, with absolute certainty, the object is a mereological part of The Ship of Theseus, but the identity of the object can or can not be The Ship of Theseus.
For example, lets say person A and person B both agree on the name of The Ship of Theseus. Person A is a harbor-master who see's it as a vessel, where as person B only uses the ship for leasure and relaxation on the pier. Let's say that a panel is removed from the ship, and is a new panel is re-attached. That panel is then embedded inside of a bench on the pier. The removed panel is an iterative subset of the ship, and therefore a partial identity of The Ship of Theseus. The bench is an iterative superset of the removed panel, which inherits the partial identity of The Ship of Theseus. However, the identity itself is up for debate despite being a mereological part of The Ship of Theseus. The same argument goes for the remaining ship with new panel. To person A, the function of the bench, which is no longer a vessel, can argue that the bench has lost the identity of The Ship of Thesesus, despite being objectively a mereological part of it. However, to person B, the function of the bench, which is still a form of relaxation on the pier, can argue that the bench has retained the identity of The Ship of Thesesus. Same goes for the remaining ship with the new panel, where the identity is up for debate.
The changes don't have to be this large however. In a Planck-time, a single orientational change of an atom or even an elecrons positional probability or spin is a dimensional change which provides a different iteration of the identity of The Ship of Theseus. Iterative subsets of wear and tear and constant, and iterative supersets of added grime and debris are inevitible. Since partial identities are inherited in an objective manner until all constituents of the original particular are no longer present, a single atom of the identity that is The Ship of Theseus can be moved around, placed anywhere, and as long as the new object this constituent is a part of holds the same function, it is up to the subject to determine whether the identity persists.
However, when we talk about identity, require the subject to have perception that the particular of interest is truly an iteration of the identity of The Ship of Theseus. Meaning, if the subject is presented a completely independent ship which has never had a partial identity of the The Ship of Theseus, since it was never an iterative subset of the original, then the subject is unaware that the ship presented can or can not have the same identity of The Ship of Theseus. Therefore, perception on iterational identity is a pre-requisite for a subject to re-assign identity to an object.
"Plasticity" is also an interesting topic, because if the ship were to creak and moan and bench, is it still the same ship due to dimensional changes? Well the argument persists: if all the atoms in the ship were re-arranged, it is an iteration of the ship, and the partial identity is still objectively inherited. However, the numerical identity which is assigned based off a subjects function has changed, so again, it is up to the subject for identity re-assignment. In addition, a ship creaking and moaning and bending likely does not change the function of the ship, for those that use the ship as a vessel, therefore the identity is likely re-assigned. One could argue that a perfectionist, who wants his/her boat is a pristine condition, will not re-assign the identity since "it's not the same" after it has gone through wear and tear. A subject is also deemed to be unreliable if they drop the identity of an objects iteration because it does not fulfill the some criteria of the object, but then after repair it does fulfill the said criteria. For example, absolute aesthetic differences in a boat for a perfectionist might say a worn down Ship of Theseus is not the same as the original, but after aesthetic improvements, the subject claims the ship is the same. This is unreliable, because the subject is using a different metric for loss of identity and re-assignment of identity; the former being loss of aesthetics, and the latter likely being the "function of it being a boat". However, if the subject's function is aesthetic differences, then the subject is reliable when the original identity is lost, it is lost indefinitely, and a new identity is assigned upon both aesthetic wear-and-tear, as well as aesthetic renovations.
This means that two individuals, person A with function of the object being "vessel", and person B with function of the object being "aesthetics of blue paint", can both lose the identity of the original ship if it has crashed and been left mangled. Upon repair, the new particular can still be used as a vessel, but let's say it has to be repainted red. Then upon repair, person A can successfully re-assign the identity of the mangled ship, who's partial identity remains objectively remains, since the function has been restored upon improvements. Person A therefore must acknowledge the mereological part (the mangled ship) being a subset of constituents making up The Ship of Theseus, while denouncing the identity. Upon restoration, the function of vessel is re-asserted and the identity can be re-assigned since both partial identity and function exist in the new particular. However, for person B, the function of aesthetics is lost upon the crash: the blue paint is left in disarray and could not be up to par for the function of person B. If the aesthetics were restored to the original paint, person B has the right for identity re-assignment since both partial identity and function exist in the new particular. However, person B would be unreliable if the identity was re-assigned to The Ship of Theseus after the ship was repaired with a different color of paint. This means that the function of person B is not the true function behind what drives person B to make proper identifications. If the function of aesthetics were in-stead a "medieval" looking ship, then various colors which fit this aesthetic can provide person B being a reliable subject.