The disturbing question that brought you here is this:
We good?
Good.
There are very good arguments in defense of either position. Here is a sketch of an exchange that might possibly take place. I'd be interested to hear how you all respond to the question, whether you do or don't read the below.
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Prima facie, it seems that it is necessary. This is because the combination of your existence with the absence (as of yet) of completely synthetic reproduction collectively decide the fact that you must have had grandparents.
But there are questions as to whether this necessity is a logical one. Firstly, is your existence logically necessary? Secondly, couldn't your actual grandparents have not been your grandparents? Third, is it logically necessary that people have grandparents, even if it's physically necessary?
Ah, but on the other hand, what this seems to turn on is the fact that we're talking about the construction "your grandparents". One can think of a great many ways in which you might not exist, or people might not have parents, but in such situations, how would we make sense of what "your grandparents" is supposed to mean? It seems reasonable to think that logical necessity should range over all accessible logical alternatives to the way we actually use our logical description of the world, rather than just every logical alternative whatsoever. So in all logical situation where "your grandparents" successfully talks about people, they talk about people that had sex.
But isn't this too weak to really be logical necessity? It seems more right to say that logic talks about the fundamental behaviour of Objects, rather than Language or Descriptions. After all, language and description are more social than an account of the most general rules of metaphysical structure should be. That is, you talk about precisely those people when you talk about your grandparents, rather than in terms of their relation to you or the social world you live in. So the logical situations you consider are those where your grandparents Exist, and there's obviously no requirement coming from their simple existence that they should have sex.
Except it's easy to use the descriptive or semantic account to account for other ways in which things could be. It's very difficult to say what it means to be the same thing in a hypothetical situation when we try to say that being one and the same object is what's important. If being exactly this object right here is what matters, and no other logical possibility would correctly describe it as being anything other, then I seem committed to metaphysical determinism, in that every property I have, I have as a matter of logical necessity. It seems a mistake to go this far and state that everything that actually happens is logically predestined. I might have had different Grandparents.
Yet the description perspective can't actually say this, because if we think that logical necessity talks about situations accessible in virtue of their descriptions, we should think logical possibility talks about the same range of situations, and in those situations, no, your grandparents are always your grandparents. Instead, you need to think of the difference in terms of your grandparents having different properties - it's logically possible that your grandparents might have been older or younger than they are. This is something that the object perspective is much better at, since you can just look at the same object in each situation and ask what properties it has. This is still a more natural interpretation of what logic does than descriptions.
... Or is it? After all, how would you go about forming logical arguments or proving logical theorems if you need to ask, of each possible situation, what properties it ascribes to the objects we're interested in? Isn't logic essentially about deduction and inference, rather than an empirical view on what is in each of these possible situations?
I'll give you a moment to overcome the face-value disturbance there."Is it, or is it not, logically necessary that your grandparents had sex?"
We good?
Good.
There are very good arguments in defense of either position. Here is a sketch of an exchange that might possibly take place. I'd be interested to hear how you all respond to the question, whether you do or don't read the below.
----------
Prima facie, it seems that it is necessary. This is because the combination of your existence with the absence (as of yet) of completely synthetic reproduction collectively decide the fact that you must have had grandparents.
But there are questions as to whether this necessity is a logical one. Firstly, is your existence logically necessary? Secondly, couldn't your actual grandparents have not been your grandparents? Third, is it logically necessary that people have grandparents, even if it's physically necessary?
Ah, but on the other hand, what this seems to turn on is the fact that we're talking about the construction "your grandparents". One can think of a great many ways in which you might not exist, or people might not have parents, but in such situations, how would we make sense of what "your grandparents" is supposed to mean? It seems reasonable to think that logical necessity should range over all accessible logical alternatives to the way we actually use our logical description of the world, rather than just every logical alternative whatsoever. So in all logical situation where "your grandparents" successfully talks about people, they talk about people that had sex.
But isn't this too weak to really be logical necessity? It seems more right to say that logic talks about the fundamental behaviour of Objects, rather than Language or Descriptions. After all, language and description are more social than an account of the most general rules of metaphysical structure should be. That is, you talk about precisely those people when you talk about your grandparents, rather than in terms of their relation to you or the social world you live in. So the logical situations you consider are those where your grandparents Exist, and there's obviously no requirement coming from their simple existence that they should have sex.
Except it's easy to use the descriptive or semantic account to account for other ways in which things could be. It's very difficult to say what it means to be the same thing in a hypothetical situation when we try to say that being one and the same object is what's important. If being exactly this object right here is what matters, and no other logical possibility would correctly describe it as being anything other, then I seem committed to metaphysical determinism, in that every property I have, I have as a matter of logical necessity. It seems a mistake to go this far and state that everything that actually happens is logically predestined. I might have had different Grandparents.
Yet the description perspective can't actually say this, because if we think that logical necessity talks about situations accessible in virtue of their descriptions, we should think logical possibility talks about the same range of situations, and in those situations, no, your grandparents are always your grandparents. Instead, you need to think of the difference in terms of your grandparents having different properties - it's logically possible that your grandparents might have been older or younger than they are. This is something that the object perspective is much better at, since you can just look at the same object in each situation and ask what properties it has. This is still a more natural interpretation of what logic does than descriptions.
... Or is it? After all, how would you go about forming logical arguments or proving logical theorems if you need to ask, of each possible situation, what properties it ascribes to the objects we're interested in? Isn't logic essentially about deduction and inference, rather than an empirical view on what is in each of these possible situations?