So, this is a common thought experiment. Known as the Ship of Theseus if you fancy, at its core it poses a simple question.
If something get's all of its components replaced, to the point where none of the original remains, is it still the same thing?

While there's likely isn't a single correct answer to this question. I'd like to hear what you think about the problem posed.
Are there cases where it's the same to you? Cases where it isn't? If you have a general answer to this question, what is it?

I'll add in my own thoughts later. But first, some of you might be wondering why this question matters at all in the first place.
Personally, I feel it is a question that is asked whenever we become attached to something that has such changes.
Objects of course can undergo such changes. But other, more abstract things such as sports teams and cultural societies can as well.
In my opinion, it is reasonable to question if something one has become attached to is truly the same, after such changes have occurred

I think that if a car got replaced it wouldn't be the same car anymore, but it will still hold the sentimental value to the owner.

The same for anything else I suppose like football players, basketball players, etc. The team is still your favorite from sentimentality but the original teammates aren't there anymore.

In this sense a car is an abstract collection of objects, so yes it's the same car.

Once a part is put on the car it becomes part of the car.
As long as the parts are being replaced it's the same car, unless you just buy a new one and scrap the previous.

There is a story by Stanislaw Lem that brings that question to a whole new level. Unfortunately I can't find that short story right now, but this abstract should give you a pretty good idea:


Now the question is: Is he just a machine because all his natural bodyparts have been replaced, even though he has the same personality etc as the original person he was before, or is he a man who should still be considered a human, even though all his bodyparts, including his whole brain, are now artificial?

I think it's a play on ambiguity, "human" can mean either "human being" or "to be human-like". He is clearly not a human - if you were to replace each part of a car with plane parts until it was entirely a plane, would it still be a car? Obviously it wouldn't be, so obviously he isn't a "human being". However he still has human nature.

It's more important to consider the context: are they asking if he's human because they want to know if he should pay taxes? Yes, he is for that purpose. Are they asking if he's human because they want to know if he requires regular dental checkups? No, he is not for that purpose.

In that legal context, I don't think it's fair to say he belongs to the salesman. Obviously their business model is dodgy at best.

Say you have a hatchet. A zombie enters your house through the door. The only weapon you have is the hatchet. You kill the zombie with the hatchet, but the handle breaks. You buy a new handle for the hatchet, and then your ex walks through the door. You hit her with the hatchet, the blade breaks. You replace the blade of the hatchet. Is it the same hatchet?

Its like having an old movie being remade. Its the same movie title; different actors/actresses and different directors. Sadly, its not the same classic. Therefore, a car that is replaced is not a car. You could play devils advocate though (replacing an organ or removing a part of a human) its still human ...right? It can go both ways, really.

Having all the parts of an object replaced to where the function isn't even the same is an interesting take on the idea.
It shows that the "object" in question can definitely become something other than what it originally was, functionally speaking.
However, a car that's had its broken radio replaced also undergoes a functional change. Just like a car that's become a plane.
Since this car underwent a functional change just like the car that became a plane, is it no longer the same thing?

Personally, I think to better answer this question one has to assign a "persona" to the objects in question.
Take Redundant's example for instance, and this time let's say that the human in question is named John.
Instead of asking if John is human, I think a better question would be: Is the end product of all those replacements still John?

Some would argue that the end product is still John, He remained John after the first step and thus must be so after every step.
Others however would claim that, since none of the original 'John' remains, the end product is merely a "collection of prostheses."
A third, more extreme, argument would be that even after the initial replacement, the end product is no longer John.

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Also going off on the theoretical side of things, has anyone here personally ever felt that something was no longer "the same" after a replacement of one of its parts? Perhaps a favorite tool of some sort? Rumor mentioned football teams, and while people generally stick with their favorite teams. Has anyone here ever "Jumped Ship" on their favorite team after a major roster change?

Our cells die and get replaced constantly, so are we all the same people we used to be?