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Ship of Theseus Paradox

Posted: Tue Oct 24, 2023 4:17 am
by HighlyIrregular II
Could someone mention Mashy if this doesn't work... @mashy

https://web.archive.org/web/20201128223 ... us-paradox
Kari wrote:Ship of Theseus paradox
Theseus owns and sails a ship. Every month, when he sails to port, he has one old plank of his ship replaced with a brand new plank. By the time 10 years has passed, not a single original plank of wood remains in Theseus’ ship. Unbeknownst to Theseus, however, the ship repairman has saved all of the old planks that he removes from Theseus’ ship.

Slowly, he constructs a new ship. By the time 10 years has passed, he has acquired every single original plank from Theseus’ ship and arranged them exactly as they were in Theseus’ original ship.

Which of the two existing ships is numerically one and the same ship as Theseus’ original ship? Is it the ship with all new parts, or the re-constructed ship with all of the original parts?
Neither is number one. The one reconstructed from original planks should be qualified as such due to the entirely new fasteners and absence of the old ones and the fact that the ship never was sailed by the original sailor when it had the new fasteners. The one with different material also should be qualified as such. Things are disassembled, moved, and reassembled all the time, but when to call them original, unqualified, should be considered on a case by case basis.

Re: Ship of Theseus Paradox

Posted: Wed Oct 25, 2023 10:15 pm
by Senseye
I'd still vote for the ship Theseus owns. And keep in mind Theseus replaced those planks for a reason. Weathered, cracked, barnacled, what have you. Some of those planks replaced in the later years were probably on their last legs.

The copy ship from recycled planks is probably pretty rickety. I wouldn't be surprised if the ship repairman didn't have to replace a few with other planks himself before he even set sail.

Re: Ship of Theseus Paradox

Posted: Sun Apr 07, 2024 4:52 am
by Utisz
Whichever answer fills your heart with joy.

Re: Ship of Theseus Paradox

Posted: Sat May 25, 2024 10:54 pm
by Senseye
I've been watching the Tally Ho Youtube videos. I just kind of stumbled across them after seeing a news clip that the boat was recently launched. I find the videos surprisingly interesting considering I am not into either boats or woodworking at all.

Anyhow, this guy bought and old wooden yacht originally built in 1910 and rebuilt it over 6 years. It's basically a ship of Thesus. He does reference the paradox in his videos a few times as well. So far (I'm only about 30% of the way through the videos) he has had to replace everything. He does keep the old wood around though, and I think he is planning to recycle what he can when constructing the interior. Still it will be mostly a new boat, but it's built based on the original plans and the boat is never really deconstructed at any point, so it always seems like he is just fixing the original boat.

Re: Ship of Theseus Paradox

Posted: Sun May 26, 2024 9:40 pm
by Ferrus
My attitude with these sorts of problems has kind of been influenced more by the late Wittgenstein (of Philosophical Investigations fame). Language is largely a social game of interaction and shared meaning through repetitive actions. The idea there is some kind of 'essence' to words largely misses the point that it is in the action not the object that the word consists. Therefore, the boat remains Theseus' simply by virtue of the fact that within the language games we play as humans interacting, the meaning of that word coheres in the ways in which Theseus can use those temporary collections of wood and how we have to treat it, that is not affected by any individual repair.