I just did that on Saturday. Shreds in all the crevices of my work bench. I found some real gems amongst the scraps though, so worth it

I think we get seduced into supposing that the *minds* of F1 and F2 are identical, even though they are material instantiated in different substrates, because we imagine that they have similar content and thus identical properties. However, this is too hasty. The mind of F2 might have all the same prior content (e.g., memories, supposing flies have memories); however, the mind of F2 has *new* and *different* content that the mind of F1 lacks: namely, whatever it (F2) is presently experiencing. Since the mind of F1 and the mind of F2 have different properties, they are non-identical.

(This reasoning raises all sorts of problems with traditional beliefs in reincarnation and resurrection!)

And here's an argument that can be used wherever someone tries to pass off a merely possible (conceivable) explanation as the actual explanation for a phenomenon. I'll refer to their merely possible explanation as P.

1. The only reason in favor of adopting P is its mere conceivability.

2. It is rational to accept a merely conceivable explanation as accurate if and only if there is no other rival alternative explanation.

∴4. It is rational to accept P if and only if there is no rival alternative explanation. [From 1 and 2]

5. For any P, there is a rival explanation, which is also merely possible (conceivable): namely, we are part of a simulated reality and all phenomenon are mere appearances without any material casual relation to one another.

∴ It is not rational to accept P. [From 4 and 5]

You can run this argument with any rival alternative hypothesis, for example, that everything I experience is a dream.

Here are some general criticisms about the form of reasoning which you noted people use.

A) Mere conceivability is not sufficient grounds upon which to make a claim about actuality/reality. It is conceivable that ghosts materialize and dematerialize at whim, but we have no independent reason to suppose that actually happens. Mere conceivability doesn't imply plausibility.

B) This seems like an ad hoc modification of the "ghosts exist and cause phenomenon" hypothesis, which is motivated by a prejudiced commitment to the hypothesis, not independent evidence or reasoning.

C) Presumably, someone who accepts that hypothesis does so because, if it were true, it would explain some phenomenon—say, an object mysteriously turning up in a weird location. There are innumerable rival conceivable explanations that can be imagined with respect to any such phenomenon, some more plausible than others. The only rational way to select one out as the most likely explanation is by appeal to independent evidence or reasons.

I agree with @duck 🌟 that even if we assume it is aware and has mental states, it isn't the self-same entity as the original. This is because the original fly (F1) and the copy (F2) have different properties. For instance, they are spatially distinct: F1 is in place 1 at time 1, whereas F2 is in place 2 and time 2. If F1 died as a result of the procedure, then. F1 doesn't exist, but F2 does.

Identity in the strict sense is numerical self-sameness, and the underlying principle is the "identity of indiscernibles," which holds that if two objects of consideration, x and y, are identical then, necessarily, any properties possessed by x must also be possessed by y. When x and y are discernable (i.e., they have different properties), then x and y are non-identical; they aren't the same thing.

Even if we imagined a human being digitally cloned in the manner described, the original and the copy would have distinct properties. They would thus be non-identical, even though the copy would *think* it was the original.

No bother at all! I love thinking about such stuff. I'll reply to your original post.

Fun question/thought!

Ah, right, that's a fun ad hoc explanation. I'll work on an argument addressing it! 😁

I think that would be *the idea* or *experience* of something taken to be a ghost, but not a ghost as such. Analogously, a mirage is an experience I take to be pool of water, but it isn't really a pool of water. In both cases, the chemicals and processes in my head constitutes an internal mental entity, not a real body.