Showing posts with label Joseph Shieber. Show all posts
Showing posts with label Joseph Shieber. Show all posts

Tuesday, 27 June 2023

Joseph Shieber's septic skepticism.

 

Joseph Shieber, a Philosophy Professor, writes in 3 Quarks
there is a difference between saying that scientific CLAIMS should stand and fall on their merits and that scientists’ success should be determined by their merits.

No. Both statements are imperative not alethic- i.e. are value judgments.  

The former statement has to do with standards of evidence and objective truth.

No. It says some particular thing should be done. It has no truth value. Some supplementary alethic claims would be needed for it to be interpreted in the manner Schieber prescribes.

One may say that 'merit' in a Scientific Claim has to do with 'elegance' not anything empirical or objective. String Theory research should be pursued even if it seems useless or is unable to generate a 'crucial experiment' to decide if it accords with what is observable.  

The latter statement, in contrast, has to do with qualities of scientific researchers correlated with advancing science, as well as with our confidence in our abilities accurately to assess those qualities.

Not necessarily. We may say 'Prof. X must be given the top job- i.e. he should gain more personal success and acclamation- because he was the most meritorious student in his batch. True, he may have accomplished nothing since, but at least the signal will be sent that if you study hard and get top marks then your success will be guaranteed'. The counter argument may be 'appoint Y to the top post. He is a lazy drunkard and didn't even pass High School. True, by some fluke, he stumbled into a field where he was able to make very useful discoveries. Still, we should reward people whose work has the merit of being useful rather than those we thought of as meritorious because they got higher marks in examinations.'  


It shouldn’t need stressing, but perhaps it does. What makes a statement or claim meritorious – its originality, interest, truth-likelihood, etc. – is different than what makes a PERSON meritorious.

No. The criteria is exactly the same. The same guys who judge an idea to be meritorious consider the person who came up with that idea to have merit. If they think if 'elegant' theories are more meritorious then they think people whose theoretical work is elegant to possess more of that quality.  

One obvious difference, of particular importance given Jussim’s own focus on objective truth, is that PERSONS aren’t truth-evaluable.

Yes they are. George Washington could not tell a lie. Donald Trump can do nothing else. Washington was truthful. Trump is not.  


Since there seems to be a great deal of confusion about this on the part of Jussim and his colleagues, I’ll state it once more: persons aren’t claims,

Claims may be about persons or things or ideas. A claim about Physics is not itself part of Physics. Thus if I say- as I frequently do, when drinking- 'Quarks are notorious for cheating on their wives' it is unlikely that anybody would mistake me for a Physicist. 

and therefore the standards for evaluating persons have to be different than the standards for evaluating claims.

We don't evaluate persons. We may attach predicates to them, for some particular purpose, on the basis of some evaluative scheme. You may say 'surely we do evaluate people? We say 'x is good' or 'y is a lazy good-for-nothing'. The problem here is that we ask 'why do you say x is good and y is lazy?' the answer turns out to be context dependent- e.g. 'I say x is good because I know he always helps the poor. I know y is lazy because he sleeps in his office and does no work whatsoever.' 

Clearly neither x nor y have been evaluated in a context independent manner. A predicate has been applied to them in a particular context. X is good when it comes to helping the poor. Y is lazy when it comes to doing his job. X may be bad because of some inherent vice which will only become apparent later on. Y may be extremely hard working when it comes to some patriotic endeavour- it just so happens he hates his job because it is boring and does nobody any good. 

 We have no general method of evaluating a person though for some particular purpose we may usefully apply a particular predicate to them. Suppose a snob says 'x is good in himself'. We are likely to suspect that the snob means that x is from an upper class background. The snob thinks the aristocrats can do no wrong. This is because the snob has a 'Structural Causal Model' such that certain predicates are intrinsic or 'necessary' with respect to a particular person. Thus a member of the nobility must be good even if all her actions appear bad. The problem is that such Models can easily be shown to be nonsense. I may say 'Washington could never tell a lie. Truthfulness was intrinsic to him'. You could easily controvert this by pointing out that there are certain scenarios or perhaps techniques of  mind control which would cause Washington to tell a lie.  


Am I unfairly reading this obvious misunderstanding INTO the paper?

Yes. The paper in question was an illiterate appeal for 'Merit in the Sciences'- i.e. please don't appoint disabled nutters who claim to be practicing ancient Voodoo Science which was cruelly repressed by Dead White Males.  

I understand that you might think I am. It might seem implausible to suppose that Jussim really would be mistaken about a paper on which he himself is a co-author. Perhaps I’m the one who’s mistaken, and the “Merit” paper itself is just a defense of scientific merit — and objective truth — against its postmodern critics. Let’s turn once more to the paper.

That would be the charitable reading. What Schieber has done is babble nonsense.  


Before we do, let’s make explicit the two different senses of “merit” that I’m accusing the authors of the “Merit” paper of conflating.

Merit has only one sense. It is a predicate which signifies excellence. Predicates can be used in all sorts of ways. I personally use 'Merit' as a mantra the repetition of which, I fondly believe, will enable me to emit more powerful farts.  

Sense 1 is the sense of “merit” that applies to CLAIMS.

Merit can be the predicate of a claim. It need not be just a mantra I use in in the hope of gaining vertical take off thanks to the propulsive power of my farts.  

More generally, we might say that a claim has merit if it’s well-constructed, interesting, supported by evidence, original, or likely to be true.

We may say that the predicate 'merit' is properly applied if the above criteria are met. But this is an arbitrary assertion. However, it may be useful enough in a particular context.  

Focusing on SCIENTIFIC merit for claims, we might be most concerned with a subset of these qualities, perhaps most particularly evidential support and truth-likelihood, among others.

No. My claims about my farts may have evidential support and have high truth-likelihood but they are not Scientific claims, or, at the very least, they have no great Scientific merit which is why my research should not attract public funding.  


Sense 2 of “merit” is the sense that applies to PERSONS.

A predicate can be applied to anything at all. One might also say pseudo-philosophical stuff like 'Only Nothingness has Merit for the Being must always be its lack of its own Becoming and is therefore devoid of Merit.' 

Since persons aren’t claims, this sense of merit is obviously different.

It is exactly the same. 'Einstein is totes cool' is obviously identical to 'The Theory of General Relativity is totes cool'.  

Nor can we simply say that persons in science have merit due to the merit of the scientific claims that they make.

Yes we can. Einstein was meritorious because his claims were meritorious.  

This is because personal merit is forward-looking:

it can be backward-looking. We now recognize Hermann Grassmann was a very meritorious mathematician. His contemporaries thought he was merely a meritorious Sanskrit scholar. He remained a High School teacher. 

we use assessments of personal merit to choose who should get accepted into our Ph.D. program, or post-doc, or who should receive this grant, PRIOR to their making the scientific claims our support is intended to underwrite.

This is an assessment of academic potential, not merit.  A friend of mine was the topper in Science Talent and then Physics at both the graduate and post-graduate level. He was rejected for a research position and thus went into the IAS. Later, he asked the man who rejected him why he did so. 'Sahib', the poor fellow replied, 'It was obvious you'd either take IAS or go off to Amrika. We had to choose a fellow who had fewer options in life.'

Of course, at some of these stages we will have earlier scientific claims of theirs that we can evaluate, but anyone who is even glancingly familiar with assessments of personal merit will grant that such assessments – even in science – have less to do with the evaluation of claims and more to do with the evaluation of signals: academic pedigree, venue of publications, previous fellowships and awards, etc.

These signals are also screening devices. Basically, you have to do boring shite to 'signal' that you will do boring shite while sucking up to your boss for the next ten years.  


My claim, then, is that Jussim’s blog post ignores the fact that the “Merit” paper invokes two distinct notions of “merit” and that Jussim collapses those two distinct notions into just what I’m calling the first sense of “merit”: the merit of scientific claims.

This may be true. The paper is utterly illiterate.  

Does the “Merit” paper really invoke two distinct senses?

No. It is stupid shit. It doesn't invoke anything at all.  

Let’s see.

Section 2 of the “Merit” paper is entitled “Merit-Based Science is Effective and Fair.” Note already that the title of the section itself invites confusion.

No. The guy is saying things are fine as they are. Let's not give tenure to woke nutters. Science is useful. It can make our lives better. Confine woke nuttiness to useless University Departments- like the one in which this Professor flourishes.

Is science merit-based because of its focus on objective truth (which Jussim, in his blog post, conflates with “scientific merit”) or is it merit-based because it rewards the efforts of scientists in proportion to the merits OF THOSE SCIENTISTS?

This is a distinction without a difference. Provided Scientists are focused on objective truths of a useful type then rewarding those who are best among them advances a meritorious type of Science.  


We find further evidence for the conflation of the two senses of “merit” in the body of section 2 itself:


On p. 4, the authors write, “merit must also be applied to evaluate research proposals and prospective students and faculty.”

are they objectively good or are they 'diversity hires' who will start babbling about Ancient Voodoo Quantum Gravity? 


On p. 5, the authors trumpet that “[m]erit-based science is truly fair and inclusive. It provides a ladder of opportunity and a fair chance of success for those possessing the necessary skills or talents. Neither socioeconomic privilege nor elite education is necessary.”

What's wrong with that? Merit based science is like merit based employment of plumbers. The fact that few Professors of Philosophy get big bucks for fixing our toilets is perfectly fair. If Philosophers want to be esteemed, they could learn plumbing.  


Finally, also on p. 5, the authors write that “[m]erit is a vehicle for upward mobility. Recruiting, developing, and promoting individuals based on their talent, skills, and achievements has enabled many who started life in disadvantaged conditions to realize their dreams and build better lives.”

Merit-based science can 'grow the pie'. Diversity hires merely corner rents. The danger is that if there are too many of them, then the pie will shrink.  

Note two features of all of these quotes. The first is that they employ the notion of merit in the second sense,

Nonsense! Nobody is saying that some people have an intrinsic quality of doing good Science. If this were the case, why give them any funding? They will produce great discoveries in any case while delivering pizzas.  

that of the qualities of a person that contribute to the advancement of science (and of that person’s career within science). The second is that they seem to imply that merit is not merely an aspirational goal of scientific institutions,

This Professor teaches in a Department which aspires not to merit or excellence but being utterly shit. 

but rather that those institutions are currently “a merit-based system,” if one with “imperfections.”

Why the scare quotes? The fact is some institutions do have very smart people who are getting valuable Scientific patents.  


In a previous essay, I’ve addressed the way in which the equivocations on the two senses of “merit” in the “Merit” paper render the argument in that paper fallacious.

Equivocation can't render an argument fallacious because a type theory can be applied- i.e. the ambiguity can be removed easily enough. If the argument is imperative, fallacies don't matter save in a protocol bound context- i.e. there is a specific regulative deontic logic.  

To put it simply, the authors of the “Merit” paper respond to criticisms that science isn’t a merit-based system in the second sense (in which practitioners’ success isn’t determined by their group characteristics)

But no practitioner's success is determined by group characteristics. This is because success or failure is determined by one's ranking within sub-groups with the same initial endowment. Thus, Scientists may explain the greater success of one of their peers by saying 'the man is a poet. He can think in a different way from the rest of us mere plodders'. 

by expressing shock that ANYONE would deny that science is a domain in which objective truth is paramount

It is shocking that some nutters say stuff like 'White Man Science is causing Physical Reality to be very naughty. Take Newton's Law of Gravity. But for it, Mummy wouldn't have gone splat on the ground that time she dropped acid and jumped out of the window. It was my tenth birthday party. There and then I decided to dedicate myself to becoming the first tenured Professor of Voodoo Quantum Gravity at Princeton.'  

— the FIRST sense of merit, as you’ll recall. (This is pretty much Jussim’s go-to move in his blog post.)

His go-to move is to appeal to common sense. Everybody knows that woke nutters are fucking over Academia. Vivek Ramaswamy is right. The West needs to pull its socks up otherwise the Chinese will eat our lunch.  


In a second essay, I addressed the question of whether defenses of merit in science, more broadly, fail to distinguish between descriptive and aspirational senses of the role of merit in science.

There is no such failure. The role of merit in Science is the same as the role of 'the pursuit of excellence' or the role of 'being the best goddam Scientist it is possible for us to be' or the role of 'not wanting the Chinese to eat our collective lunch.' This role is an aspiration. It is a reasonable aspiration to have because a good description of Scientific progress to date shows that the role of merit in Science has indeed worked in this way. 

No country advanced in Science through wokeness or by going in for 'diversity hires'. On the other hand, getting in a lot of smart darkies from Africa or Asia or wherever proved highly efficacious.  

To put it briefly, I suggested that believing science in fact to be a merit-based system (in the second sense of “merit”) is likely problematic,

How? Even if it isn't so, this belief militates to making it so.  

while I nevertheless held out the hope that embracing merit as an aspirational goal of science might contribute to making science — as the authors of the “Merit” paper put it — “truly fair and inclusive.”

Fuck being fair and inclusive and sensitive to the needs of kids who get triggered by the mention of 'homework' due to the fact that trillions of American citizens are literally homeless. What's more, they are constantly being raped and shot by the Police. How can any Society which claims to be civilized inflict 'homework' on kids? Also, how come Biden hasn't undergone gender reassignment surgery like he promised?  


In what remains of this essay – hopefully the last on the “Merit” paper – I want to extend the discussion of the descriptive vs. aspirational readings of merit,

this is just the distinction between actual and potential merit. There is no confusion here. It is obvious that a person with potential merit may never actually do anything meritorious because the Professor of Voodoo Quantum Gravity rapes the fellow to death as part of a ritual sacrifice to Baron Samedi. 

considering a further way in which the confusion of these two readings provides fallacious support for the arguments in the “Merit” paper.

The argument this fool is providing support for is that teaching Philosophy makes you stoooooopid. 


The problem I want to address here is that the “Merit” paper plays on the confusion of descriptive vs. aspirational readings of merit. Here is a one-sentence summary of the paper, by an ethicist at Merck who Jussim approvingly cites in his blog post:

The central assertion of “In Defense…” is that merit should serve as the primary criterion for evaluating and assessing scientific claims,

reject Voodoo Quantum Gravity because it is useless shit. Don't reject mathsy theories of Quantum Gravity which can be tested by a 'crucial experiment' in the not too distant future.  

rejecting the notion of substituting it with social engineering or identity-based policies.

Don't hire an ex-con to be Professor of Voodoo Quantum Gravity just because he is disabled, trans, and ticks various other affirmative action boxes in between raping his colleagues to death. 


Note that this gloss of the central assertion of the “Merit” paper involves the ASPIRATIONAL reading: “merit SHOULD serve as the primary criterion.”

Why? Because, where it served such a criterion in the Past, Scientific research proved to be highly utile.  

The quotes from section 2 of the paper itself, however, suggest the DESCRIPTIVE reading: “[m]erit-based science IS truly fair and inclusive. It PROVIDES a ladder of opportunity … Neither socioeconomic privilege nor elite education IS necessary,” or “[m]erit IS a vehicle for upward mobility. Recruiting, developing, and promoting individuals based on their talent, skills, and achievements HAS enabled many …”

This is reasonable. There may have been a time when very few women or dark skinned people had STEM subject Nobel prizes. But now every community has role models of this type.  

The problem with this confusion, of course, is that it invites fallacious defenses of the argument in the “Merit” paper. When someone criticizes what the “Merit” paper actually says – that science IS a meritocracy – the defenders of the “Merit” paper reply that they’re only saying that science SHOULD be a meritocracy.

That may be the case if this is an argument between illiterate fools. However, one can always build a 'steel-man' (as opposed to 'straw-man')  version of the argument and see if it can be demolished. Is it  true that American Science from the Thirties onward was more successful than German Science? Yes. The Americans would hire Jews and darkies like Chandrashekhar. The Nazis chased them out of the Academy regardless of their great merit. Einstein had to run away from Berlin to Princeton. Many others, including non-Jews, followed him. By the mid Fifties you had Chinese origin American Physics Nobel Laureates. Sadly, Madam Wu- who lacked a penis- was denied this accolade. It is a fact that many women don't have testicles. How the fuck can they hope to be balls to the wall Scientists? 

The protestations in the “Merit” paper about the meritocracy that is contemporary science – and the conflations of the descriptive and aspirational understandings of merit in science – are strikingly similar to related protestations by political conservatives that the United States is now a “post-racial” democracy, as described in Ronald Brownstein’s recent Atlantic essay, “The Post-Racial Republicans.”

Guys like Vivek Ramaswamy. Nothing wrong with that.  


In that essay, Brownstein writes – alluding to a quote from Barack Obama – that “If political leaders ‘pretend as if everything’s equal and fair,’ Obama said, ‘then I think people are rightly skeptical’ of their commitment to ensuring equal opportunity.”

Obama, a Law Professor familiar with the Coase Posner 'Law & Econ' tradition, knew the work of African-American economists which enabled charges of statistical discrimination to be proved. This meant- e.g. Pigford v Glickman- big damages for discriminated against communities and, also, successful 'pattern and practice' investigation followed by 'consent decree' based reform. 

Sadly, Obama did too little to safeguard Black Lives and thus contributed to the virus of  'wokeness' which he criticized albeit in a timid manner. 

Despite the occasional nods to the fact that contemporary science isn’t perfectly equal and fair, it certainly seems that the authors of the “Merit” paper, with their insistence on the supremacy of merit in science, seem equally deserving of our skepticism.

Who gives a fuck about the skepticism of a Philosophy Professor? We are content if they don't masturbate in public.  


The authors of the “Merit” paper are a mixed group. Some of them are prominent scientists – including Nobel prize winners. Others of them are, at this point, basically professional “anti-woke” trolls. Given the fallacious reasoning and equivocations shot through the “Merit” paper, it is hard to avoid the conclusion that, in writing the paper, the “anti-woke” trolls had the upper hand.

This shit may be intended to be anti-anti-woke, but it merely exhibits the Professor's stupidity and inability to reason.  

Tuesday, 28 August 2018

Joseph Scheiber on why I can't be racist

Prof. Joseph Scheiber writes in 3Quarks
Mac Donald, in her diagnosis of where the social justice warriors have gone astray, schools “the victims and the gatekeepers of victim culture” on what they’ve misunderstood about language:
The meaning of language arises in a particular context and with reference to authorial intention, implicit or explicit. … It was a breakthrough in philosophy, starting with Plato, to recognize the conventional nature of language—that a linguistic sign is not the same thing as the signified. That understanding opened the way for the sophisticated study of language and interpretation, known as hermeneutics. A return to a belief in word magic, however, whereby words directly impinge on their referents, radically limits human expression and imagination.
According to Mac Donald, the social-justice leftists have forgotten that the meaning of language isn’t fixed, but relies on “authorial intention” and “particular context”. Mac Donald discusses in particular “the elaborate rituals around the ‘n-word’” as evidence for the sort of belief in “word magic” that she criticizes. 
Scheiber believes this response reveals 'a glaring lack of understanding of how language works.' He says
“Speech acts” is a term coined by the British philosopher J.L. Austin to characterize the ways we “do things with words”. In addition to rules governing the syntax, or grammar, of a language, and its semantics, or meaning, there are also hidden regularities underlying the pragmatics of language — how the words we utter can bring about predictable effects in the world around us. 
The problem here is that 'predictable', for pragmatics, must be Bayesian and based on the user's priors- even if they are wildly off the mark. I may believe that my jihad against the Iyengars of Dollis Hill is succeeding because all the Iyengars I drunk dial to roundly abuse for their blasphemous denial of the possibility of a jivanmukta confess to actually being Iyers who killed and stole the identity of the original occupants of the house and so, for fuck's sake, could you move on to harassing Iyengars in a different post code?

Since Bayesian priors can't be common knowledge- otherwise speech acts would be redundant- it follows that, if either 'income effects' are non-neglibible or 'hedging' features, then pragmatics must be anything goes.


Schieber believes otherwise- He says if McDonald is right
then it would not be a feature of the way language normally functions that someone, regardless of their intention, could either (1) fail to perform a particular speech act or (2) be unable to avoid performing a certain speech act — due largely to structural, social facts.
This is quite mad. I fail to perform particular speech acts in German coz I don't know German. I can't avoid performing certain speech acts in English because I may be sent to prison if I don't. McDonald never denied this plain fact. Nobody ever has. Austin's notion of a 'performative speech act' is one which can be substituted for. Thus, if it falls to me to nominate the Fuehrer of the German Chapter of my Anti Iyengar Jihad, some translator will do the job for me and there will be some protocol by which I give assent.

Schieber gives the following example of a person being unable to perform a particular speech act regardless of their intention.
Prior to the 1980’s, it was legally impossible in most states of the United States for a husband to rape his wife. This is because the law contained what was called a “spousal rape exception”.
Does Schieber think a woman couldn't say 'he raped me' just because she was married to the rapist? Even the Judge could say 'you, Sir, are a depraved and evil rapist. However, such being the law of the land, I can't sentence you for that crime. So I'm giving you the maximum sentence for grievous bodily harm.'
To put it another way, prior to the 1980’s, a wife uttering “No” or “Stop” to her husband would have had no – legal – right to expect that her words would have their intended effect.
Schiber is being silly. Plenty of women said 'no' or 'stop' and quite rightly expected their words to have the intended effect. Why? Rape is unconscionable. There are extra-legal sanctions which can be applied. Even from the legal standpoint, marital rape would have had consequences- for e.g. in a divorce case or claim for alimony. Mental suffering, even from an act not illegal in itself, can still feature in a civil case.

Schieber next tries to imagine a situation where 'it is impossible for that speaker, whatever his intentions (contra Mac Donald), to avoid performing certain speech acts when using certain words.'
Suppose you’re the boss of a crime syndicate, and your henchmen regularly engage in nefarious practices to solidify your hold on your crime empire. One day, thinking about a person who has been a thorn in your side for a while, you muse out loud, in the presence of your henchmen, “That guy has been a pain in my neck for far too long. It would be better if he’d just disappear”. The next day, you read in the paper that the person has turned up dead.
Schieber is being silly. The boss of a crime syndicate is known to kill any of his henchmen who misunderstand him or, indeed, fail to read his mind. Scheiber's scenario is not a realistic. Suppose we are henchmen. I say to you 'listen, we'd better go bump off that guy. The Boss just ordered us to do so.' You reply, 'Did he say that to you explicitly? Think about it. Why has the Boss not killed this guy  already? He must have a reason. Let us clear it with the Boss first. Don't forget he'll kill us and our families if we bump off a guy he's still got a use for.'
Assuming that it was your henchman who did the deed, then you bear at least some responsibility for the person’s death.
Hilarious! Schieber thinks Crime Bosses care about their 'responsibility' for some wiseguy's death!
This strikes me as being true even if, in fact, you did not intend for your henchmen to draw the inference that you were ordering a hit when you said that you wanted the person to “disappear”. Given your role and status, and the power that you have over your henchman, you should have been more aware of the effect that your words would have.
Wow! Schieber thinks Mob Bosses aren't aware of the effect their words have. What he doesn't get is that killing more people or getting more of them killed is what increases the effect of the Don's words.
What this case illustrates is that one’s social position and status can endow their words with a power that the same words, when uttered by others, would not have. When you, the crime kingpin, wish out loud that a person who is a nuisance to you would disappear, you can make yourself culpable for that person’s murder. When I, a meek philosophy professor, wish out loud that an annoying colleague would disappear, nothing happens.

The Mob Boss's Bayesian priors are likely to be common knowledge for his henchmen- because otherwise they just get killed and replaced- thus his performative speech acts are likely to be more, not less, intentional from the point of view of pragmatics.

By contrast, a meek philosophy professor may have a homicidal nutjob in his class- indeed, I think the thing is pretty much de rigueur at them fancy-shmancy East Coast Collidges- and so his speech act is more likely to be unintentionally performative. To be clear, a henchman checks before killing a wiseguy. A crazy sophomore doesn't. Why? The Mob boss will kill you if you screw up. Your Philosophy Professor, will probably just say something sarky about your grasp of the later Wittgenstein.


Scheiber thinks
The same words, with the same literal meanings, can have completely different effects – and have them in systematic and predictable ways. And the reasons for those different effects – and for why those effects differ systematically and predictably – are “institutional and systemic”, rather than resulting from the speaker’s intentions or the literal meaning of what he says.
This is foolish. Either the speaker is stooopid- like me-  and has crazy Bayesian priors and thus doesn't understand anything about the 'institutional and systemic' features of Reality- in which case the systematic and predictable effect of his speech acts is people tittering politely and edging away- as happens to me at cocktail parties ; or else, where salient performative speech acts occur, 'institutional and systemic' facts have already been factored into the speaker's utterance leaving a pure intentionality whose pragmatics all concerned parties will have invested time and trouble to accurately decipher.

Scheiber says-
The cases show that Mac Donald is wrong because they show that, regardless of intention, some speakers are either incapable of performing certain speech acts or unable to avoid performing certain speech acts.
In other words, Scheiber is saying a raped wife couldn't say she was raped whereas the truth is she could. Moreover, if she said it to her brother, the Mafia Don, guess what would happen to the rapist? He'd sleep with the fishes with concrete boots and his dick in his mouth.

Similarly, the Don who is blowing off steam against a made man won't actually be making a 'performative speech act' because his henchmen know they have to be double and triple sure before pulling the trigger because their own necks are on the line.
In other words, Mac Donald focuses too much on the intention of individual speakers, and ignores the ways that forces outside of those speakers can shape the impact that their words may have.
It is perfectly reasonable for MacDonald to do so. Language wouldn't be much use to us if it genuinely suffered from the signal extraction problem Schieber attributes to it on the basis of his assumption of the universality of a stupidity unique to himself.

Actually, Shieber probably isn't really stupid. He is just pretending to be so as to be able to make the following claim-
  Plausibly, much of what makes speech racist is that it functions to reinforce and sustain an historically established social hierarchy built on subordinating “whole groups of people, based on hoary stereotypes”.
No group of people has ever been subordinated on the basis of 'hoary stereotypes'. They have been subordinated on the basis of beating and killing.

The fact that people like me continue to claim that Darwin was wrong- the Earth does not go round the Sun because my grandpappy was a monkey and climbed the sky tree and cut the string- does nothing to reinforce and sustain anything whatsoever. 
The history of the N-word, for example, is inextricably linked to a society that brutalized black bodies and saw people of African descent as less than human.
That particular Society got rich of African and indigenous peoples. It did so by beating and killing them- not by saying rude things. Then it found a way to make even more money by letting such people move up into more productive jobs and professions. No doubt, the courage and patriotism African Americans showed on far flung battlefields was also a factor. The N word or the K word or the I word (for Iyengar) don't matter very much.
So in fact it is Mac Donald who indulges in magical thinking when she supposes that a single person’s intentions, however innocent or well-meaning, could be enough to change the racist effects of using that word. A white person using that word cannot, simply through the force of his or her own will, erase that history.
The history they can't erase is that of the Sixties. Also, getting stomped on discourages the thing. America has its own rules. I don't suppose they'd tolerate Tottenham Hotspur's traditional chant 'We are the Yids' or 'Go Yiddoes' either. Indeed, with the rise of anti-semitism in England- something few of us ever thought we'd see- the younger generation is turning against the use of certain epithets us old geezers use among ourselves with affection and nostalgia for the good old days when instead of women wearing hijabs, we were obliged to put a brown paper bag over our heads in order to get our end off. My friends deny that any such thing happened to them probably coz they were all virgins. My memory is that even the sluttiest girls insisted on it- probably in the mistaken belief that it constituted 'safe sex'.

Returning to Scheiber, this is the punchline to his article-
There is no corresponding history of the systematic subordination of white people by black and brown people on which to draw.
 There is a corresponding history of white people beating the fuck out off black or brown people who tried to subordinate them- or, that failing, simply running away, like the French from Haiti.

It is a good idea to beat up or run away from a bunch of guys coming at your people shouting racialist or confessional slurs. 'Fighting words' are exactly that- you either fight or run away or else get so ground down you can't run away.

The fact that something hasn't happened doesn't mean a particular course of behaviour is irrational or mischievous. It may be the principal reason the thing hasn't happened.
So, while someone from an historically oppressed group can be criticized for employing false generalizations about white people, for indulging in unfair or even hateful negative characterizations, or – yes – for their boorish trolling of white people, they cannot engage in racist speech against white people.
Sure they can, if their Bayesian priors are such that they believe they can win in a fight and get to subjugate white people. Take ISIS type nutters. They thought they could win. So they went on spewing hate speech and knifing people till even the Brits lost patience and cracked down on their brand of racism. This was 'eusocial'. Even if a guy can't beat you up, it makes sense to stop him from working himself up to make the attempt. Fewer of his bones get broken and you too are saved time and trouble.

In Economics there is a theory of wasteful competition. Virtue signaling is an example. Some Jewish intellectuals in London felt they had to be more Anti Zionist than the Palestinians. Poor old Jeremy Corbyn was currying favour with them and ended up spewing vicious lies against Israel which has the same right to self-determination as any other nation. He's now being dragged over the coals for it. For the rest of us, this type of competitive (but, I believe, insincere) anti-semitism is simply a nuisance. It is perfectly proper for the Law to step in and curb it. On the other hand, my sacred jihad against the Iyengars must be allowed to continue. Far from ever having oppressed any Iyengar, the only one I was able to press a little forced me to wear a paper bag over my head. Come to think of it, what happened to me was statutory rape. My 'Yes! Yes! Yes!' actually meant, according to Scheiber, 'No! No! No!'.