This is a fascinating argument — thank you for sharing it! I think it’s particularly interesting to consider it in the context of metaethical theories that don’t fall neatly within the realist paradigm but share some of its features, like R.M. Hare’s universal prescriptivism (see Freedom and Reason [1963] and Moral Thinking [1981]). However, I also think this probably shouldn’t lead most discounting realists to abandon their moral view. My biggest issue with the argument is that I suspect (though I am still thinking this through) that there exist parallel arguments of this form that would purport to disprove all of philosophical realism (i.e. including realism about empirical descriptions of the natural world). I think statements rejecting philosophical realism are pretty epistemically fraught (maybe impossible to believe with justification), which leaves me suspicious of your argument. (It’s worth noting here that special relativity itself is an empirical description of the natural world.)
I have a feeling that the right way of thinking about this is that the rise relativistic physics changed the conventional meaning of a “fact” into something like: a true statement for which its truth cannot depend upon the person thinking it within a particular inertial frame of reference. Otherwise, I think we would be forced to admit that there are not facts about the order in which events occur in time, and that seems quite obviously inconsistent with the ordinary language meanings of several common concepts to me. I know that relativity teaches that statements about time and duration are not objective descriptions of reality but are instead indexical reports of “where the speaker is” relative to a particular object, similar to “Derek Parfit’s cat is to my left,” but (for basically Wittgensteinian reasons) I do not think that this is actually what these statements mean.
Ultimately, if you’re someone who, like me, believes that a correct analysis of the question, “What is the right thing to do?” must start with a correct analysis of the logical properties of the concepts invoked in that sentence (see R.M. Hare, especially Sorting Out Ethics [1997]), and you believe that those logical properties are determined by the way in which those concepts are used (see Wittgenstein’s Philosophical Investigations [1953]), then I think this argument is mainly good evidence that the proper understanding of what moral realism means today is the following: “Moral realism holds that moral statements are facts, and the truth of a fact must be universal within the inertial frame of reference in which that fact exists; that is, that truth cannot depend upon the person thinking the fact within that inertial frame of reference.”
Thanks for that comment and your thoughts! I am unfortunately unfamiliar with the works of Hare, but it sounds interesting and I might have to read up on that.
I totally agree with you, that there are statements to which we assign truth values, that depend on the frame of reference (like “Derek Parfit’s cat is to my left”, or the temporal ordering of spacelike separated events.)
I would also not have a problem with a moral theory, that assigns 2 Utilons to an action in one frame of reference, and 3 Utilons in another.
I do however believe that there are some statements that should not depend on the frame of reference.
We have physical theories to predict the outcome of Measurements, so any sensible physical theory should predict the same outcome to any measurement, whichever frame of reference we use to describe it.
We have moral theories to tell us what actions we should do, so any sensible moral theory should prescribe the same actions, whichever frame of reference we use to describe them.
If you however do not have that requirement to a moral theory, I see that discounting realists would not have to change their views.
This is a fascinating argument — thank you for sharing it! I think it’s particularly interesting to consider it in the context of metaethical theories that don’t fall neatly within the realist paradigm but share some of its features, like R.M. Hare’s universal prescriptivism (see Freedom and Reason [1963] and Moral Thinking [1981]). However, I also think this probably shouldn’t lead most discounting realists to abandon their moral view. My biggest issue with the argument is that I suspect (though I am still thinking this through) that there exist parallel arguments of this form that would purport to disprove all of philosophical realism (i.e. including realism about empirical descriptions of the natural world). I think statements rejecting philosophical realism are pretty epistemically fraught (maybe impossible to believe with justification), which leaves me suspicious of your argument. (It’s worth noting here that special relativity itself is an empirical description of the natural world.)
I have a feeling that the right way of thinking about this is that the rise relativistic physics changed the conventional meaning of a “fact” into something like: a true statement for which its truth cannot depend upon the person thinking it within a particular inertial frame of reference. Otherwise, I think we would be forced to admit that there are not facts about the order in which events occur in time, and that seems quite obviously inconsistent with the ordinary language meanings of several common concepts to me. I know that relativity teaches that statements about time and duration are not objective descriptions of reality but are instead indexical reports of “where the speaker is” relative to a particular object, similar to “Derek Parfit’s cat is to my left,” but (for basically Wittgensteinian reasons) I do not think that this is actually what these statements mean.
Ultimately, if you’re someone who, like me, believes that a correct analysis of the question, “What is the right thing to do?” must start with a correct analysis of the logical properties of the concepts invoked in that sentence (see R.M. Hare, especially Sorting Out Ethics [1997]), and you believe that those logical properties are determined by the way in which those concepts are used (see Wittgenstein’s Philosophical Investigations [1953]), then I think this argument is mainly good evidence that the proper understanding of what moral realism means today is the following: “Moral realism holds that moral statements are facts, and the truth of a fact must be universal within the inertial frame of reference in which that fact exists; that is, that truth cannot depend upon the person thinking the fact within that inertial frame of reference.”
Thanks for that comment and your thoughts! I am unfortunately unfamiliar with the works of Hare, but it sounds interesting and I might have to read up on that.
I totally agree with you, that there are statements to which we assign truth values, that depend on the frame of reference (like “Derek Parfit’s cat is to my left”, or the temporal ordering of spacelike separated events.)
I would also not have a problem with a moral theory, that assigns 2 Utilons to an action in one frame of reference, and 3 Utilons in another.
I do however believe that there are some statements that should not depend on the frame of reference.
We have physical theories to predict the outcome of Measurements, so any sensible physical theory should predict the same outcome to any measurement, whichever frame of reference we use to describe it.
We have moral theories to tell us what actions we should do, so any sensible moral theory should prescribe the same actions, whichever frame of reference we use to describe them.
If you however do not have that requirement to a moral theory, I see that discounting realists would not have to change their views.