Could someone explain to me what exactly is meant by the phrase "fact of the matter about" (or "no fact of the matter about")? Another variant is: "(no) fact of the matter as to". In some cases, there's no "about" or "as to" at the end (e.g. see last example below).
This is a phrase I have run into many times, especially in philosophical discourse, but I have not been able to infer its meaning (I'm not a native speaker of English), nor have I been able to find a satisfactory definition for it.
The immediate motivation for this question is reading Block and Kichter's 2010 review of What Darwin got wrong, by Fodor and Piattelli-Palmarini, where the phrase is used repeatedly. (The fact that the authors resort to the same [IMO somewhat awkward] phrase repeatedly is what strongly suggests to me that this phrase has for them a very precise technical meaning.) Here are the occurrences of the phrase in this review (italics in the original, bold formatting mine):
Their specific charge is that, with respect to correlated traits in organisms—traits that come packaged together—there is no fact of the matter about which of the correlated traits causes increased reproductive success. In other words they appear to be making the very ambitious claim that whenever there are correlated traits there is no fact of the matter about which of the traits causes any effect. ...
If Fodor and Piattelli-Palmarini acknowledge the evidence that favors the camouflaging-color hypothesis over the moth-larvae and moth-mobility hypotheses, they will have to say that the biologists have not been imaginative enough—that they have overlooked some other correlated trait for which there could be no fact of the matter about whether it, or the black coloration, caused the reproductive success.
What exactly could this trait be? One possibility, suggested by remarks in some of Fodor’s previous writings, would be that there are two different properties: being black, on the one hand, and matching the environment on the other. Is there a fact of the matter as to which of these causes the reproductive success?
...Evolutionary theory, Fodor and Piattelli-Palmarini say, contains, at its core, a causal notion—selection-for—that picks out the properties that cause increased reproductive success. They then declare that there is no fact of the matter about what causes increase reproductive success when the candidate properties are correlated with others. But correlation is omnipresent, so evolutionary biology totters.
Also, one of the comments added to this review uses several instances of the same phrase:
To the best of my knowledge, Fodor has a view of causation where a causes b just in case there is a covering law: A -> B, such that a has A and b has B. So whenever a causes b, there'll be a fact of the matter [sic] which property or properties of a are such that in virtue of them, a caused b, namely all those properties X such that there is a law X -> B, where a has X and b has B (for some B). So according to Fodor, there are lots of facts of the matter about what causes what, and in virtue of what.
But when there's no covering law, there's no real causation. Fodor's example is that of history. Suppose Frenchman tend to lose battles and all and only Frenchman are short. Is it because they're short or because they're French that they lose? Or because of some other property correlated with Frenchness and shortness? Well, none of the above. There's no fact of the matter because there are no laws of the form: French -> lose or short -> lose. There just aren't any laws of history, not even ceteris paribus laws.
This is also Fodor's view regarding natural history (evolution). White polar bears proliferate. Is it because they're white or because they're snow-colored? No fact of the matter *because* there's no law of the form snow-colored -> proliferate, and no law of the form white -> proliferate. There aren't even ceteris paribus laws of this form.
BTW, when I've tried to find the meaning for this expression via Google, I have come across a few pages where someone asserts that "the fact of the matter" is just another way to refer to "the truth". The simplicity of this definition does not jive with the fact that the authors find it necessary to use the phrase repeatedly, even though it is neither succinct nor particularly colloquial. (IOW, why didn't they simply use some suitable form of "the truth" instead?)