Theseus's paradox

[Z]

The ship of Theseus, also known as Theseus's paradox, is a paradox that raises the question of whether an object which has had all its components replaced remains fundamentally the same object. Plutarch questioned whether the ship would remain the same if it were entirely replaced, piece by piece. Centuries later, the philosopher Thomas Hobbes introduced a further puzzle, wondering: what would happen if the original planks were gathered up after they were replaced, and used to build a second ship. Which ship, if either, is the original Ship of Theseus?

If you replace all of the individual parts of something over time, one by one, is it still the same object? For example, if you replace the glass in a window with new glass; and then later on replace the wooden frame with a new wooden frame - is it still the same window? It's in the same place as the old window and it performs the same function as the old window, but all of the individual parts have changed over time. Does that mean it is different or the same, because the individual parts add up to a whole (i.e. the window)? Is an object an object or is it the sum of all its parts?

[Jesus.]

Trigger: And that's what I've done. Maintained it for 20 years. This old brooms had 17 new heads and 14 new handles in its time.

Sid: How the hell can it be the same bloody broom then?

Trigger: Theres the picture. What more proof do you need?

http://ukcomedyquotes.files.wordpress.com/2011/12/triggers-broom.jpg

Philosophy being debunked by trigger.

The minute you change something, then it can't fundamentally remain the same thing. It's function and structure remain unchallenged, but technically it is different.

[Z]

What if you take all of the original parts, bit by bit, to build something new? The replacement model has overtaken the original over time and therefore parts of the replacement model have presumably been in use for longer than parts of the original model, so while it is fundamentally a different object, it's still the same model if only in name, surely?

[Kizzy]

My daughter was telling me about her philosophy work on logic yesterday, let's have a go...
premise 1
the ship has new glass
premise 2
the ship has new frames
conclusion
the window is new

Both premise are true so the conclusion for the argument that the window is new is vaild...

Is that right?

I would say neither are the original object as they are both replications of the original structure as built without any alterations initially.

[Jesus.]

What if you take all of the original parts, bit by bit, to build something new? The replacement model has overtaken the original over time and therefore parts of the replacement model have presumably been in use for longer than parts of the original model, so while it is fundamentally a different object, it's still the same model if only in name, surely?

I suppose it depends how "micro" we go into it. The minute the original structure is altered in any meaningful way, then it instantly becomes different.

It is the same object " a house", but with a different structure. I think viewing the thing as an overall "object" demeans the fundamental problem a philosopher will be trying to address.

I think if I address the "new boat" puzzle in your op, then I'd view it as this:

If you break down the original boat, whilst replacing the parts with new parts, then build the first boat again with the original parts, then you have 2 different boats, but one uses the original parts. Part of that original boat will be things like brackets and nails, that would be non-transferable. However, if you look at it superficially - it's the exact same boat. But being the pedant that I am, it's completely different.

I really like your posts, I often find myself disagreeing with you, but you put your points across in a way that makes me want to continue the discussion, and requires me to think about how I formulate a response.

[Tregard]

Every 10 years all of the atoms that comprise your body are totally replaced, after a gradual constant change over the decade. Does that mean you are not still you?

[Jesus.]

Every 10 years all of the atoms that comprise your body are totally replaced, after a gradual constant change over the decade. Does that mean you are not still you?

Why would that be the case?

A 20 yr old you will be/is/was taller than a 2yr old you, so you're absolutely different, but you're the same person. Macro vs Micro.

[AnnieK]

I really don't think I have logical mind at all...this thread is making my head hurt!

[Kizzy]

Every 10 years all of the atoms that comprise your body are totally replaced, after a gradual constant change over the decade. Does that mean you are not still you?

The cells are cloned not replaced I thought?

[Z]

I really don't think I have logical mind at all...this thread is making my head hurt!

My favourite way to break it down is this:

The band "Sugababes" started out as Siobhan Donaghy, Mutya Buena and Keisha Buchanan in 1998. In 2001, Donaghy left and was replaced by Heidi Range; they carried on under the name Sugababes. Buena left in 2005 and was replaced by Amelle Berrabah, and then in 2009 Buchanan was replaced by Jade Ewen. In 1998 the Sugababes were Siobhan, Mutya and Keisha; in 2009 they were Heidi, Amelle and Jade. This was a gradual process, which meant that new members were not brought in overnight. Heidi spent 7 years as a member of the Sugababes before Keisha was replaced and their integrity was brought into question, compared to the 3 that Siobhan spent in the band. Surely that makes her more of a Sugababe than Siobhan ever was; yet she was not an original so does she have any right to be using the name Sugababes?

[Z]

I suppose it depends how "micro" we go into it. The minute the original structure is altered in any meaningful way, then it instantly becomes different.

It is the same object " a house", but with a different structure. I think viewing the thing as an overall "object" demeans the fundamental problem a philosopher will be trying to address.

I think if I address the "new boat" puzzle in your op, then I'd view it as this:

If you break down the original boat, whilst replacing the parts with new parts, then build the first boat again with the original parts, then you have 2 different boats, but one uses the original parts. Part of that original boat will be things like brackets and nails, that would be non-transferable. However, if you look at it superficially - it's the exact same boat. But being the pedant that I am, it's completely different.

I really like your posts, I often find myself disagreeing with you, but you put your points across in a way that makes me want to continue the discussion, and requires me to think about how I formulate a response.

That's what happens when I'm stuck in an office all day with nothing to do :D

[Jesus.]

I really don't think I have logical mind at all...this thread is making my head hurt!

http://www.thomlinson.cumbria.sch.uk/images/library/The%20Megabytes/Josh/ball%20of%20string1.gif

This should keep you busy.

[AnnieK]

http://www.thomlinson.cumbria.sch.uk/images/library/The%20Megabytes/Josh/ball%20of%20string1.gif

This should keep you busy.

Don't be mean....:laugh:

[Jesus.]

Don't be mean....:laugh:

I'm just pulling your hair in the playground.

[Nedusa]

The ageing process is the bodies inability to continually replace molecules in the body. Were it to continue the process indefinitely we would in theory live forever.

But as we are continually replacing body parts over time I guess this means that we are not the same person we used to be but we ARE the same person albeit continually replacing all our major parts.

Has this helped explain the paradox........ probably not !!

[Kizzy]

The ageing process is the bodies inability to continually replace molecules in the body. Were it to continue the process indefinitely we would in theory live forever.

But as we are continually replacing body parts over time I guess this means that we are not the same person we used to be but we ARE the same person albeit continually replacing all our major parts.

Has this helped explain the paradox........ probably not !!

we don't know for certain if the cell that replaces the dying cell was present before during or after apoptosis though?