The claim might just need correction to say, “Many philosophers say that simplicity is a good thing but the requirement is not enforced very well by philosophy journals” or something like that. I think I believe you, but do you have an example citation anyway? (SEP entries or other ungated papers are in general good; I’m looking for an example of an idea being criticized due to lack of metaphysical parsimony.) In particular, can we find e.g. anyone criticizing modal logic because possibility shouldn’t be basic because metaphysical parsimony?
In terms of Lewis, I don’t know of someone criticising him for this off-hand but it’s worth noting that Lewis himself (in his book On the Plurality of Worlds) recognises the parsimony objection and feels the need to defend himself against it. In other words, even those who introduce unparsimonious theories in philosophy are expected to at least defend the fact that they do so (of course, many people may fail to meet these standards but the expectation is there and theories regularly get dismissed and ignored if they don’t give a good accounting of why we should accept their unparsimonious nature).
Sensations and brain processes: one of Jack Smart’s main grounds for accepting the identity theory of mind is based around considerations of parsimony
Quine’s paper On What There Is is basically an attack on views that hold that we need to accept the existence of things like pegasus (because otherwise what are we talking about when we say “Pegasus doesn’t exist”). Perhaps a ridiculous debate but it’s worth noting that one of Quine’s main motivations is that this view is extremely unparsimonious.
From memory, some proponents of EDT support this theory because they think that we can achieve the same results as CDT (which they think is right) in a more parsimonious way by doing so (no link for that however as that’s just vague recollection).
I’m not actually a metaphysician so I can’t give an entire roll call of examples but I’d say that the parsimony objection is the most common one I hear when I talk to metaphysicians.
“Make things as simple as possible, but no simpler.”—Albert Einstein
How do you know whether something is as simple as possible?
In terms of publishing, should the standard be as simple as is absolutely possible, or should it be as simple as possible given time and mental constraints?
It still may be hard to resolve when something is as simple as possible.
So modal realism (the idea that possible worlds exist concretely) has been highlighted a few times in this thread as an unparsimonious theory but Lewis has two responses to this:
1.) This is (at least mostly) quantitative unparsimony not qualitative (lots of stuff, not lots of types of stuff). It’s unclear how bad quantitative unparsimony is. Specifically, Lewis argues that there is no difference between possible worlds and actual worlds (actuality is indexical) so he argues that he doesn’t postulate two types of stuff (actuality and possibility) he just postulates a lot more of the stuff that we’re already committed to. Of course, he may be committed to unicorns as well as goats (which the non-realist isn’t) but then you can ask whether he’s really committed to more fundamental stuff than we are.
2.) Lewis argues that his theory can explain things that no-one else can so even if his theory is less parsimonious, it gives rewards in return for that cost.
Now many people will argue that Lewis is wrong, perhaps on both counts but the point is that even with the case that’s been used almost as a benchmark for unparsimonious philosophy in this thread, it’s not as simple as “Lewis postulates two types of stuff when he doesn’t need to, therefore, clearly his theory is not as simple as possible.”
The claim might just need correction to say, “Many philosophers say that simplicity is a good thing but the requirement is not enforced very well by philosophy journals” or something like that. I think I believe you, but do you have an example citation anyway? (SEP entries or other ungated papers are in general good; I’m looking for an example of an idea being criticized due to lack of metaphysical parsimony.) In particular, can we find e.g. anyone criticizing modal logic because possibility shouldn’t be basic because metaphysical parsimony?
In terms of Lewis, I don’t know of someone criticising him for this off-hand but it’s worth noting that Lewis himself (in his book On the Plurality of Worlds) recognises the parsimony objection and feels the need to defend himself against it. In other words, even those who introduce unparsimonious theories in philosophy are expected to at least defend the fact that they do so (of course, many people may fail to meet these standards but the expectation is there and theories regularly get dismissed and ignored if they don’t give a good accounting of why we should accept their unparsimonious nature).
Sensations and brain processes: one of Jack Smart’s main grounds for accepting the identity theory of mind is based around considerations of parsimony
Quine’s paper On What There Is is basically an attack on views that hold that we need to accept the existence of things like pegasus (because otherwise what are we talking about when we say “Pegasus doesn’t exist”). Perhaps a ridiculous debate but it’s worth noting that one of Quine’s main motivations is that this view is extremely unparsimonious.
From memory, some proponents of EDT support this theory because they think that we can achieve the same results as CDT (which they think is right) in a more parsimonious way by doing so (no link for that however as that’s just vague recollection).
I’m not actually a metaphysician so I can’t give an entire roll call of examples but I’d say that the parsimony objection is the most common one I hear when I talk to metaphysicians.
Why shouldn’t it? I haven’t seen any reduction of it that deals with this objection.
Would that be desirable? If a contributor can argue persuasively for dropping parsimony, why should that be suppressed?
Surely that should be modal realism.
“Make things as simple as possible, but no simpler.”—Albert Einstein
How do you know whether something is as simple as possible?
In terms of publishing, should the standard be as simple as is absolutely possible, or should it be as simple as possible given time and mental constraints?
You keep trying to make it simpler, but you fail to do so without losing something in return.
It still may be hard to resolve when something is as simple as possible.
So modal realism (the idea that possible worlds exist concretely) has been highlighted a few times in this thread as an unparsimonious theory but Lewis has two responses to this:
1.) This is (at least mostly) quantitative unparsimony not qualitative (lots of stuff, not lots of types of stuff). It’s unclear how bad quantitative unparsimony is. Specifically, Lewis argues that there is no difference between possible worlds and actual worlds (actuality is indexical) so he argues that he doesn’t postulate two types of stuff (actuality and possibility) he just postulates a lot more of the stuff that we’re already committed to. Of course, he may be committed to unicorns as well as goats (which the non-realist isn’t) but then you can ask whether he’s really committed to more fundamental stuff than we are.
2.) Lewis argues that his theory can explain things that no-one else can so even if his theory is less parsimonious, it gives rewards in return for that cost.
Now many people will argue that Lewis is wrong, perhaps on both counts but the point is that even with the case that’s been used almost as a benchmark for unparsimonious philosophy in this thread, it’s not as simple as “Lewis postulates two types of stuff when he doesn’t need to, therefore, clearly his theory is not as simple as possible.”