IBM and the Ship of Theseus

[Tribal]

The “Ship of Theseus” is a thought experiment: if you have Theseus’s famous ship and eventually replace every last board, fastener, sail, and so on until nothing from the original ship remains, is it still the Ship of Theseus? If not, when did it cease being so? (And: what if you saved all the original pieces over time and put them back together? Is it now the Ship of Theseus? Is the one you’d been working on it? Are both/neither?

Let’s say I’m restoring a Unicomp Classic from 5/21/2010. I get a Lexmark-for-IBM case from 1995, scrounged keycaps from a 1986 IBM, and a 2021 replacement membrane from Unicomp and install them. How old is my Model M? Is it IBM, Lexmark, or Unicomp? Or is it just a franken-M with no true brand or date of birth?

Perhaps put another way, is there a crucial part that, if replaced, results in a different keyboard?

[zrrion]

How old is the keyboard is simple enough for a board with such variety of parts: date of final assembly. The age of parts is interesting for sure, but final assembly transformed it from parts and into a keyboard. For dating vintage boards you don't date the board on when the chips were made, you don't go by the case's mold date, you don't go on the age of the caps/switches, or any other individual part, you go by either date of manufacturer, date it passes QC, or the date of official refurb. You're not authorized for official refurb, but the work was sufficiently transformative to represent a beginning of life for this new board.

Is it an IBM, Lexmark, or Unicomp? Or is it just a franken-M? Is a leading edge a leading edge board because they made 100% of the parts? The plate, membrane, controller, flippers, and barrels are all unicomp though so I'd say it is closest to unicomp than anything else, but the board is fundamentally yours.

[Muirium]

In an IBM: definitely the barrel plate. That’s the heart of the keyboard. Cherries and Alps are harder to say. To me: they are similarly the plates I suppose.

Cases, caps and switches (in lesser platforms) can all obviously be swapped while the board remains the same. PCBs, controllers and cables too. It’s the plate I guess where I see it all coming together. That’s the core of the thing. Replace it and you have another keyboard at last.

[E3E]

As for what the heart of a keyboard is: I'd say it depends on what makes up the strongest identifying features of the individual keyboard in question. What parts to it are truly unique from a design perspective? Which are special to you? It's subjective. Very subjective. That varies between keyboards, even of the same type. Sometimes the case is the most unique aspect, sometimes the keycaps, or the PCB, plate, etc.

Regarding the main topic though: Once an original part is destroyed or replaced, it's no longer original to that specific manufacture. It has been changed, objectively.

So what's important to you? If it captures the same essence or the part is one that matches well from another keyboard of the same kind, for me, that would work, especially if the keyboard I started with was partial or incomplete.

Ultimately, if your goal is restore something to match its original condition, but it's impossible to use original exact to the number, to the day of mfg parts, but you can otherwise replicate it using official parts and whatever means necessary, then I'd say you've succeeded.

It's just not totally original anymore and no it is not that exact keyboard (versus stock) anymore; it's now modified. I'd say it's okay enough to refer to it by its original final assembly date and model no. Most wouldn't bat an eye at that, but it's technically not original anymore in terms of parts in the strictest sense.

Per your example, If you construct an entire keyboard from parts that stem from many different dates, then I'd say it becomes more of a custom build with components from various date ranges. It is not, at that point, an OEM product, even if made from OEM parts. It contains various parts from various keyboards made at different times. It is not any one of those parts or dates. If a majority of the keyboard is sourced from a specific manufacture date, then you can state it exactly as that: a keyboard built from parts mostly from [this date].

Your finished build would still be a "Model M" because that's what it amounts to, regardless. It's not quite IBM, not quite Lexmark or Unicomp, but a lovely little chimera that's still an M. It wouldn't have a traditional IBM birthdate, just date of completion of your personal rebuild.

For my custom builds, like my Miramasa, shown below, I have constructed it out of many vintage but also modern parts. I'd date it as when the build was completed, using components from the '80s, '90s, and 2010s - completed in 2016.

[shallot]

My F AT was actually finished in 2021, as you can see from the test log on the back of the assembly :v

[E3E]

Of course IBM would be ones to time travel in the 80s. That's why we have synthwave

[XMIT]

The point of the "Ship of Theseus" thought experiment is that the notion of authenticity is entirely arbitrary and in the eye of the beholder. So, the answer is up to you.

[Muirium]

In Scotland, where all important events occur of course, we have our own more practical and manly equivalent of the Ship of Theseus. For a hundred years we had to keep painting the Forth Bridge or it’d rust and collapse! Every time the crew reached one end, they’d start back at the other. If they didn’t: no more Forth Bridge!



After a hundred years or so its founding curse was broken by advancements in paint chemistry. Otherwise known as Alchemy!

Anyway, I digress. At no point in any of this were any of us too thick to reckon, rightly, where bridge was. Right there, ya metaphysical miscreants! You can even ride across it on the train!

(The wiki page is pretty good. Even I never knew the Alan Turing link.)

[Polecat]

Hmmm. George Washington's axe. The head's been replaced three times, the handle twice. But then they say he never actually chopped down that cherry tree...so is it the question that's flawed, rather than the definition?