It's all about the deep questions.
Third Principle on the Structure of Possible Worlds: Real Modality Part 2
For this part, I will first give a negative argument against the primary reason that people give for saying there are genuine possibilities. Then, I give one additional positive argument for the thesis that there are no genuine mere possibilities. Lastly, I give some ramifications of the view
Against Modal Intuition
Most philosophers don’t even address the “heavy” modal problem because they assume that it has a positive answer. Why? Their intuitions. How could metaphysicians be satisfied on accepting such a substantive claim on such a weak basis? At least, what I care about is what reality is like; I don’t care at all about modeling my intuitions/conceptual scheme of reality if I have no reason to believe that that model is modeling reality! Furthermore, there seems to be a conclusive case against thinking that this particular intuition “tracks” reality in any way. If it did, there would have to be some sort of causal link between the truth maker of genuine possibility and our having that intuition, which there evidently seems to not be. We have reason to give a non-zero weight to our intuition if and only if the probability that we have those intuitions given that they are true is greater than the probability that we have those intuitions given that they are false. Since there is no causal link, these probabilities are equal. In other words, there exists a bijection between those worlds where we have the intuition and the intuition is true and those worlds where we haven’t the intuition and the intuition is false. It therefore seems to be that metaphysicians relying on this particular intuition are straightforwardly violating a basic notion of rationality.
The Explanatory Problem for Inflationism
If other worlds genuinely could have been the case, it is a perfectly natural question to ask, “why did this reality obtain as opposed to some other one?” If any question deserves an explanation, this one does. At least to me, this would seem to be the central problem in all of metaphysics, if inflationism is true. So, what can serve as the reason why this reality obtained as opposed to some other one? The reason can’t be within reality, since this would be entirely circular. Reality would first have to obtain for there to be a reason why it obtained. Therefore, there can be no reason. However, before drawing this conclusion to fast, let us entertain the possibility that there can be reasons “outside” of reality in some sense, although this does seem to me to be nonsensical. We can use the analogy of God “picking” one world out of all of the possible ones to be actualized (although for me this doesn’t suffice since God would be just part of reality). The question reduces to the question of whether God had reasons for his choice. But then, here the second horn of the dilemma comes into play. If there was some reason God picked this world as opposed to any other world, then the other worlds wouldn’t have been picked! And since they wouldn’t have been picked, they are not possible after all! I do want to admit this isn’t a conclusive argument against the view. One can hold a “no-explanation” view that there is just no reason why this reality obtained as opposed to another. I can’t bite such a big bullet.
So, the heavier problem of modality has been answered. What about the lighter problem? Well, the first thing to note is that this wouldn’t be much of a problem that carves nature at the “joints”. It would be more for our conceptual scheme then anything else, since we have already admitted that there is no heavy modal problem. Admitting this, why bother with elaborate theories of possible worlds, combinatorialism, etc.? Why not just say X is possible iff it is not a priori that not-X? It even seems that we can keep on talking about modal claims like we do. We can have counterfactual analysis of causation with light modal claims. We can even keep on saying things like “it is possible that I’m a computer scientist” in a lighter, more ontologically neutral, yet not content-empty way. Furthermore, no problems of transworld identity and counterparts comes up! Ironically, the deflationist view seems to be on better footing than the inflationist view! We can resume the talk, without all the misleading pseudo-debates. We can have our cake and eat it too. (For those who are familiar with the view, I would call this developed view “Deflationist Modal Rationalism”.