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The ship of Thesus

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Edited by Michael Gumbrell, Wednesday, 20 Sep 2017, 07:37

My first book had some interesting reading in it last night.

The ship of Theseus.

Is it still the same ship if every plank of wood in the ship has been replaced because of decay?

The book talked about numerically indentical and quailitive indentical.

Looking very breifly at the philosophical arguements around if the Theseus would be the same ship or the restoration means she is not the same ship.

That made me think of the 3 ships just a couple of miles away from me, in Portsmouth dockyard.

The Mary Rose, 500 years old snd preserved. No replacement of any of the wood. Just preservation work rakes place.

The HMS Victory. A classic ship of Theseus. Virtually all the wood has been replaced over the last 275 years.

The HMS Warrior also has had much of her wood replaced. However as an iron clad hull, much of her metal work is orginal.

All very intetrsting stuff.

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Hi Michael

That's a really interesting point. 

As a non-philosopher (social sciences are more my thing!), my gut instinct is that it is still the "same" ship, even if all the original timber has been replaced.  My ex-hsb was Royal Navy, so I have a little insight on this.  It's only my personal opinion of course, but I think it's the spirit of a ship that makes it the same vessel, rather than the physical make-up of it. 

I'm thinking here of ships like the Ark Royal - there have been several ships of that name over the years/centuries, but they all have that undefinable spirit and quality about them just because they're called Ark Royal.  I'm sure that to have served on Ark Royal would undoubtedly be something to be proud of, whichever incarnation it was.

That's my tuppence-worth anyway! smile


Michael Gumbrell

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Hi Alison. 

I am doing Politics, Philosophy and Economics, so i get to mix a Art with two social science's.

We are both aboard the FASS boat.

I sgree with you, individual ships and ships that share a nsme all exsist on s continum.

The story of the vessel continues, planks and crews change, but the story of the ship carries on.

I really enjoyed the thought experiments around the paradox of the ship of Theseus. Or to give it another nsme, the paradox of the Victory, Warrior or Triggers broom.

Intetesting stuff,

And nice to meet and discuss with you.

Me in a rare cheerful mood

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I used to get cross with this stuff in A222.  They invented philosophy questions and insisted the personal or societal answers could not be considered and thereby created a supposed paradox only maintained by an artificial set of constraints comprising any refusal to recognise an answer.

The ship of Theseus, with all the parts replaced, is the ship of Theseus.  It will have continued operating as the ship of Theseus during that time of repair, the object is the thing in this context, not the sum of the parts.  Just as the Mersey ferry is one of a number of vessels that have been repaired and replaced over time.

When the bloke in the shipbuilder's scrapyard takes all the thrown away parts from the ship of Theseus and builds a ship from it, no it is not the ship of Theseus.  It is Honest Odo's dodgy cut-n-shut ship made out of old ship of Theseus parts.

Theseus owns a ship, this is it.  If he sells it and buys a new one, that becomes the ship of Theseus.

The Enterprise is the vessel in Star Trek.  It is always the Enterprise.  Is the Enterprise the ship in Star Trek?  Yes.  No matter what size, shape, number, it is still the Enterprise, the Star Trek vessel.  Whether you think NCC-1701 or NCC-1701-D is the definitive Enterprise is personal taste, they are all the Enterprise, the ship of Star Trek.  You can even have two USS Enterprises in the same dock if you want, they are both the Enterprise, the ship of Star Trek.

"The ship of Theseus" is not a collection of atoms in a particular configuration.  It is a label we attach to something.  We can move that label, duplicate it or destroy it.  The collection of atoms is merely a temporary configuration of some matter that we point at for a while with that label.  Things and their allocated names are not the same thing.

But don't put that down in an A222 TMA, they'll tell you you're wrong.

With insincere apologies to Wittgenstein, philosophy is the bewitchment of our intelligence by means of language.