[danbruc]

You are using identity yourself all the time. You just mentioned philosophy, this TV series, gold, that ship and that plank, and on close inspection there would probably be a thousand more cases in your last post where you relied on identity.

Identity is one of the most fundamental concepts, without it you would have a hard time splitting the universe into more than one distinct piece in order to reference and talk about them. You can only refer to this TV series because it is an entity with identity, equal to itself and not equal to any other thing in the universe.

And yes, it is a very hard problem, as Theseus illustrates one can not simply define identity using the atoms or some other kind of parts something is made of in the general case to define identity. But that just shows the difficulty of the problem, not that identity is a useless idea.

I am not a philosopher but it seems to me that without a notion of identity or equality you can not have more than one distinct thing. Well, probably someone has spend his entire life thinking about that, so maybe there are alternatives to identity and equality?

[osullivj]

Quine: "no entity without identity" & "to be is to be the value of a bound variable". IMHO the neatest summation of a rigorous approach to the interface between mathmatical logic and ontology. That's why "Quine is our hero", as one of my lecturers back in the 80s, Jeremy Butterfield, used to say.

[Blikkentrekker]

> You are using identity yourself all the time. You just mentioned philosophy, this TV series, gold, that ship and that plank, and on close inspection there would probably be a thousand more cases in your last post where you relied on identity.

And none of those are scientific inquiries where I proffer rigorous methodology.

> Identity is one of the most fundamental concepts, without it you would have a hard time splitting the universe into more than one distinct piece in order to reference and talk about them. You can only refer to this TV series because it is an entity with identity, equal to itself and not equal to any other thing in the universe.

Yet various exact scientific inquiries work very well without assuming it's existence or that there be a difference between same and different identity.

> And yes, it is a very hard problem, as Theseus illustrates one can not simply define identity using the atoms or some other kind of parts something is made of in the general case to define identity. But that just shows the difficulty of the problem, not that identity is a useless idea.

It is a very simple problem. The answer is: “identity is a pseudoscientific concept that is “not even wrong”.”.

It is so vague, so bereft of any definition that the claim of whether that two references share the same identity is “not even wrong”.

> I am not a philosopher but it seems to me that without an notion of identity or equality you can not have more than one distinct thing. Well, probably someone has spend his entire life thinking about that, so maybe there are alternatives to identity and equality?

And that is why the various models of exact sciences typically to not require that such arbitrary lines be drawn of what is and isn't a different “thing”.

[danbruc]

And none of those are scientific inquiries where I proffer rigorous methodology.

But it obviously works, I did not confuse the ship and the plank or you and the TV series, which tells us that identity is a useful concept we can use to navigate the world. The fact, that it may be hard to formalize the concept and deal with all the edge cases, does not change that.

Yet various exact scientific inquiries work very well without assuming it's existence or that there be a difference between same and different identity.

Can you provide any example?

It is a very simple problem. The answer is: “identity is a pseudoscientific concept that is “not even wrong”.”.

It is so vague, so bereft of any definition that the claim of whether that two references share the same identity is “not even wrong”.

I am pretty sure people doing homotopy type theory [1] would disagree. And I am just picking this because it has gotten quite a bit of attention in recent years but people have put a lot of work into thinking about identity and equality over the centuries.

And that is why the various models of exact sciences typically to not require that such arbitrary lines be drawn of what is and isn't a different “thing”.

Same as above, I would like to hear an example.

[1] https://en.wikipedia.org/wiki/Homotopy_type_theory