Theoretical or speculative science is not philosophy

Continuing the topic of unification, it seems that Kim Sterelny's book The Evolved Apprentice (2012) could be an actual example of naturalistic philosophy that has as its goal the unification of the sciences. In my previous post I was sceptical of philosophers' ability to contribute to such a project, and made the point that in any case it should be called theoretical science, not philosophy.

Here is Tim Lewens' review:

"As philosophers have begun to express scepticism with traditional briefs for their discipline - including various forms of conceptual analysis and metaphysical speculation - some have suggested instead that our role should be to draw together the results of many different sciences, with the aim of providing a balanced and coherent image of our place in nature that is both conceptually disciplined and properly grounded in empirical enquiry. One problem levelled at this synthetic mission-statement for philosophy is that it makes the business too demanding: it is simply implausible that anyone can attain the necessary critical mastery of such a wide range of fields. Kim Sterelny's wonderful new book, which knits together results from ethnography, theoretical biology, cognitive science, and biological anthropology, constitutes an intimidating possibility-proof for others who would aim at such syntheses." (Review of Kim Sterelny: The Evolved Apprentice, 2013)

Note how useless mainstream philosophy is for this kind of work:

"there is comparatively little philosophy in this book, if by 'philosophy' one means the sort of discussion that goes on in the pages of our professional journals. There isn't even much philosophy of science." (ibid.)

So far, so good. But then Lewens tries to argue that this should still be called philosophy:

"The account is nonetheless philosophical, partly because of its speculative nature, partly because Sterelny's synthesis is an armchair activity parasitic on the empirical work of others, and partly because the sort of conceptual ground-clearing loved by philosophers is essential as the elements of Sterelny's story are combined." (ibid.)

Why would being speculative make it a philosophical account instead of just a general scientific hypothesis waiting to be confirmed by further empirical inquiry? And why would being an armchair activity make it philosophical instead of just ordinary theoretical science? After all, there is a lot of useful scientific activity that is quite far away from direct empirical work, i.e. theoretical and computational neuroscience as opposed to wet-lab experiments, and nobody would call it philosophy. "Conceptual ground-clearing" is also an essential part of ordinary scientific research and cannot be separated from the empirical part. Philosophy does not "own" conceptual clarification.

Leave unification and big-picture thinking to scientists, not philosophers

It is amazing how metaphilosophy keeps repeating itself. Philosophers still put forward metaphilosophical ideas that have already been criticized in a compelling way in 1927.

Some contemporary philosophers think that it is the job of philosophy is to provide a unified picture of how all the different sciences hang together:

"Scientists tend to compartmentalize knowledge, even while continuing to award high prestige to general and elegant theories, leaving philosophers with the possible role ... of showing how the compartments jointly make up a single building." (Don Ross: Will scientific philosophy still be philosophy? 2013)

"I think of the integrative role as a relatively permanent one for philosophy, but it is one that is especially relevant now, because of specialization in intellectual life. Maybe as late as the mid 19th century, a person could know a large fraction of what there was to know without greatly sacrificing their pursuit of detailed work in one field. This is probably no longer possible; now it is necessary to specialize in generalism" (Peter Godfrey-Smith: On the Relation Between Philosophy and Science, 2013)

"Philosophical generality is especially crucial for an interdisciplinary field such as cognitive science, in that it can attempt to address questions that cross multiple areas of investigation, thereby helping to unify what otherwise appear to be diverse approaches to understanding mind and intelligence." (Paul Thagard: Why Cognitive Science Needs Philosophy and Vice Versa, 2009)

This is, of course, an old idea. Here is Wilfrid Sellars in 1962:

"What is characteristic of philosophy is not a special subject-matter, but the aim of knowing one's way around with respect to the subject-matters of all the special disciplines." (Philosophy and the  Scientific Image of Man)

In my view, there are two reasons why this idea is absurd.

First, philosophers are hopelessly unfit for the job. They lack the scientific training and tools that would allow them to truly understand the complex interconnections between the different sciences. It is true that scientists specialize. But at least they specialize in a science, not in the latest scientifically empty puzzle in analytic philosophy. Furthermore, scientists don't have to waste any of their time on philosophy so they have more time to learn about science in general.

Second, even if philosophers were competent enough to unify the sciences, it wouldn't be philosophy. It would be simply theoretical science, completely disconnected from contemporary analytic philosophy.

My first point had already been made long before Sellars wrote his article:

"it is the traditional business of philosophy to look into the concepts and assumptions of the sciences and to put the results of their inquiries together into one intelligible whole. Someone must undertake this, and the philosopher seems to be the person. But can we say of the flesh-and-blood philosopher who actually exists that he is qualified for the job. Here there are doubts. If the philosopher is to act as critic and co-ordinator for the sciences, he must have a firm hold on their distinctive nature, concepts, and methods. ... How much mathematics does the philosopher commonly know? ... philosophers often undertake to discuss them without such knowledge." (Brand Blanshard: Philosophy in American education: Its tasks and opportunities, 1945)

A. d'Abro made the point already in 1927(!):

"there is room for a more general type of philosopher - a super-philosopher, as it were - whose facts would comprise all the spheres of human knowledge  

... 

[Scientists] alone, in view of their wide knowledge of facts and their mastery of the rigorous mathematical mode of thinking, are in a position to co-ordinate the apparently disconnected results furnished by experience and by reason. If, then, a super-philosophy is to be attained, it would appear that the most successful results would ensue from a work of collaboration between the scientists of the various branches of knowledge." (The Evolution of Scientific Thought, 1927)

Quantum gravity research desperately needs metaphysicians' help!

Here are some philosophers suggesting that metaphysics could be useful in the search for a final theory:

"it is precisely the fact that physics is not yet complete that metaphysicians right now have something to contribute. In expressing what they take to be the best ways of filling out current physics, of working through these theories' implications and trying to understand them, this can help the physicist better understand her own theories. Indeed this may give the physicist reason to favor one or another venue in developing and extending current theories and revising them."(Alyssa Ney: Neo-positivist metaphysics, 2012)

 "Let me also stress that metaphysics can be prospective as well as retrospective. It needn't only follow where science leads. ... And by exploring different conceptions of time, philosophers open up new possibilities to consider in devising a theory of quantum gravity." (Craig Callender: Philosophy of Science and Metaphysics, 2011)

"there is no shame in the fact that metaphysicians find themselves with a wide variety of acceptable theories for a given entity. ... having a range of conceptual options increases the depth and breadth of our understanding of the world, and should ultimately result on more successful final theories. If physics has a long way to go, it will need metaphysics for most of the way." (L. A. Paul: Metaphysics as modeling: the handmaiden's tale, 2012)

This is just ridiculous. Progress in fundamental physics will consist of mathematical innovation, doing more and more accurate experiments and developing new physical (not metaphysical) hypotheses and finding out ways to empirically test them. How on earth could metaphysicians, with their lack of practical know-how in experimentation and mathematical modeling, their scientifically outdated, metaphorical and untestable theories, their trout-turkeys and hypergunk, and their never-ending intuition mongering, make any kind of useful contributions to such a project?

Physicists are not and should not be interested in contemporary metaphysics:

"Physicists are aware that their subject raises many conceptual difficulties, but do not imagine that either a training in philosophy or a discussion of these difficulties with philosophers would help in solving them. ... Never before, I believe, have philosophy and the natural sciences been so far apart." (Michael Dummett: The Place of Philosophy in European Culture, 2012)

"the scientist seeking insights in pursuit of unification will find nothing of any use in most of the literature produced by analytic metaphysicians. ... Contemporary discussions ... are completely disconnected from his concerns because those debates utilize no information about the world that has been learned from any sciences. They may as well be occurring on regions of space-time that are space-like separated from those in which we ... sit; we recognize nothing in them that corresponds to any reality we can measure." (James Ladyman and Don Ross: The World in the Data, 2013) 

Ney's idea that metaphysicians could help the physicist better understand her own theories reminds me of this remark by Bas Van Fraassen:

"metaphysicians interpret what we initially understand into something hardly anyone understands." (The Empirical Stance, 2002)

 Lets leave the task of trying to understand physical theories to physicists instead of intuition-mongering non-physicists.

"Einstein was interested in philosophy, therefore, philosophy is scientifically interesting"

The fact that Einstein and other physicists of his era were interested in philosophy in no way implies that contemporary physicists should likewise pay attention to philosophy. While it is true that in previous times, scientists were much more interested in philosophy, this was just because back then philosophy was more fashionable in the wider cultural environment. Physicists are not interested in philosophy anymore because they are wiser, not because they have become philosophically unsophisticated philistines.

"an interest in philosophy was just part of the normal intellectual cultural environment in Germany at the time. Today, things are quite different, and the stars of modern science are more likely to have been brought up on science fiction. ... the physicist who is a quantum mechanic has no more knowledge of philosophy than the average car mechanic. ... In this century at least, science has generally been totally unaffected by the philosophers of science, though some Nobel laureates claim that their work has been greatly influenced by Popper." (Lewis Wolpert, The Unnatural Nature of Science, 1994)

Scientists should ignore philosophical ideas about scientific methodology

Scientists are acting wisely when they don't pay attention to philosophical ideas about scientific methodology:

"most economists have a low opinion of 'Methodology'. ... The 'Methodology' that most economists ignore is, in fact, philosophy." (Don Ross: Lionel Robbins and broad positivism: all the philosophy an economist needs, 2007) 

"Skillful trade-offs between generality and accuracy rely crucially on the modeler's insight, judgment and experience - in a word, on her pragmatic professional know-how - not on applications of a priori methodological rules as some philosophers imagine." (Don Ross et al, Midbrain Mutiny, 2008) 

Besides their practical know-how, all the methodology (that is, positive advice about how to do economics) they need can be found in textbooks and other non-philosophical books written by scientists themselves:

"An example of a document that is surely methodological in the straightforward sense of the word and yet has plenty of respect around my department [Ross is an economist] is Hayashi's Econometrics (2000). ... it is ... a set of recipes telling an economist how to test models against data and how to gather and measure data in such a way that they can be used to test models of the kinds economists build. 

... 

those figures who have had the largest influence on economists' working understanding of their practice ... were at most occasionally influenced in tangential ways by philosophers. In their work, methodology does not come apart from first-order economic theorizing." (Don Ross: Lionel Robbins and broad positivism: all the philosophy an economist needs, 2007)

 Don Ross is both a practicing scientist and a philosopher so he knows what he is talking about when he discusses the relationship between science and philosophy. According to him, the only more "philosophical" (in Ross' sense) book economists should read is Lionel Robbins' Essay on the Nature and Significance of Economic Science, but notice what he says about it:

"the Essay is not methodology except in a negative sense. That is, from a practical point of view there are merely a few things it advises economists not to do: they shouldn't try to infer sweeping generalizations from quantitative historical data, or set out to empirically test the basic postulates of economics such as the general positive correlation between relative prices and sizes of ratios of demand to supply. 

... 

Note that Robbins mentions not one philosopher in the Essay. 

... 

the considerations that drive argumentation in the Essay all come from economics." (ibid.)  

 There does not seem to be much that "normative" philosophy of science could offer to scientists, as one of my fellow anti-philosophers often points out.

The minimum amount of philosophy a scientist needs

(Spoiler: the minimum amount is zero)

Words of wisdom:

"Scientists should avoid philosophy as much as possible, and wherever in the pursuit of knowledge anyone can do science instead of philosophy, they should." (Don Ross et al, Midbrain Mutiny, 2008)

Does this mean that sometimes scientists, if they want to be good scientists, cannot avoid philosophy? Perhaps. Perhaps there is a minimum amount of philosophy that scientists need. According to Ross, all they need is a broadly positivistic, philosophically minimalistic attitude, which consists of an epistemic version of verificationism, avoidance of philosophical principles and theses imposed on science, and an attempt to understand how the different fields of science are or should be related to their neighboring disciplines:

"though I reject positivist phenomenalism (and reductionism), there are aspects of positivist philosophy of science that are independent of this, and are worth trying to preserve. One of these is explicit concern for the unity of science. Another is a (nonfanatical) measure of verificationism: it a putative hypothesis doesn't seem to hinge in any way on a physical intervention somebody could make in the world to explore its consequences, it is hard why the hypothesis in question should be taken seriously." (Ross, Economic Theory and Cognitive Science, 2005)

"Economists generally doubt that philosophy is relevant to what they do. Their instinct in this respect is sound, though the simple expression of it just given is a bit too crude. Minimal self-consciousness about an activity - the extent of self-consciousness needed to be able to meaningfully say "we do economics, not psychology or sociology or demography" - implies a minimum degree of philosophical sophistication." (Ross: Lionel Robbins and broad positivism: all the philosophy an economist needs, 2007)

This is just an expression of his idea of what philosophy of science in general should be like:

"the very point of good philosophy of science is to examine the wider landscape of separated disciplinary silos in search of potentially unifying themes." (Ross, Economic Theory and Cognitive Science, 2005

Of course, for a naturalist, the study of the interconnections between scientific disciplines (i.e. questions of reduction) will itself have to be empirical too:

"The basic "good naturalist" grounds for any philosophical claim about science must be some set of empirical facts or other." (ibid.) 

"Any successful argument for a local reduction, and any successful argument for the irreducibility of some other class of phenomena, must be based strictly on contingent empirical data. Nothing at all about what does or doesn’t reduce to what can be established by philosophical reflection." (Ross et al, Midbrain Mutiny, 2008)

It seems to be that this kind of inquiry would be just theoretical science (or metascience), not philosophy. So it turns out that all the "philosophy" a scientist needs is actually science!

There is nothing radical about anti-philosophical scientism

In fact, pro-philosophical, armchair-friendly traditionalism is much more radical. Contemporary philosophers' projects are downright hubristic:

"From our perspective the ambition of contemporary metaphysicians [and their project of describing the fundamental nature of reality by the power of pure reason] is much greater than ours. Where we seek to synthesise into a unified picture insights from fundamental physics and the special sciences, based on the empirical knowledge accumulated by a vast collective effort, many metaphysicians imagine they can discover deep general truths while paying no attention to the results and conclusions of their colleagues in the lab. This is not just ambition but hubris." (Ladyman & Ross, Protecting Rainforest Realism, 2010)

If analytic philosophy had never existed and somebody would invent it now, when we already have contemporary science, and demand a place for it in our best universities, she would be considered radical and crazy. Given how successful science is and how unreliable intuitions are, why on earth would we need an intuition-based extra-scientific discipline to provide us with competing or complementary pictures of reality?

What justifies scientism?

Scientism is an anti-philosophical position. It does not leave room for anything that could still be called philosophy . So why should we accept such a "radical" position? Here are some reasons:

1. Scientism is a coherent position. It is at least another perfectly respectable option on the table. There shouldn't be any more disagreement about this than there is disagreement about the fact that both humean and non-humean accounts of laws of nature are coherent.

2. Scientists can do good science without knowing anything about contemporary philosophy. Philosophy is unnecessary. Science works. Scientists do not need to solve any artificial problems invented by philosophers, such as the "problem" of induction or the debate between realists and antirealists. There may be some important, more abstract higher-level questions in science, but they are intra-scientific, and theoretical science is enough to answer them.

3. Pre-scientific intuitions and hunches are unreliable, and philosophers do not have any other source of evidence. It is all just epistemically worthless intuition mongering.

4. The core areas of philosophy, metaphysics and epistemology, can be replaced by science. If they can be replaced by science, they should, since science has clear practical benefits and much better epistemic credentials.

5. Philosophy wouldn't have any worth even if somehow, magically, philosophers would be able to organize their varying, culturally specific "expert" intuitions into a consistent set, solve their problems, and converge on universal and eternal philosophical truths.

When we have a coherent scientistic option on the table, and there are no good positive reasons to think that philosophy is necessary, useful, or epistemically worthwhile, the reasonable move is to just grab it, without waiting for any "deeper" justification or a final knock-down argument.

Are the methods of analytic metaphysics scientific?

Some analytic metaphysicians claim that they are actually employing the same methods as scientists, such as inference to the best explanation and appealing to theoretical virtues, the only difference being that metaphysicians address questions that are either "more fundamental" or more general than the questions that scientists address. An example:

"Those who argue that metaphysics uses a problematic methodology to make claims about subjects better covered by natural science get the situation exactly the wrong way around: metaphysics has a distinctive subject matter, not a distinctive methodology. The questions metaphysicians address are different from those of scientists, but the methods employed to develop and select theories are similar." (L. A. Paul, Metaphysics as modeling: the handmaiden's tale, 2012)

The philosophers of science Gordon Belot and James Woodward do not buy it:

"If ontology follows a version of the scientific method, the relevant version is a degenerate case - and, I think, we should be suspicious of the credentials of its output." (Belot: Healey, Method and Metaphysics, Pacific APA) 

"Papers appearing in Science, Nature or the Physical Review, even when they report the discovery of novel 'entities' or structures such as the Higgs boson ... are very, very different in terms of content, argumentation, and evidence appealed to than what is found in [analytic metaphysics]." (Woodward: Methodology, ontology, and interventionism, 2014) 

"If standard philosophical accounts of theory-testing, evidence, explanation and so on recognize no sharp difference between [empirical science and analytic metaphysics] ... that reflects the inadequacy of those standard philosophical accounts rather than indicating that [analytic metaphysics] is just ordinary science, pursued at a higher level of abstraction." (ibid.)

I do not buy it either. If analytic metaphysicians really do employ scientific methods, then why do they so often end up making claims that are empirically false according to current science? And why don't scientists feel any need to study analytic metaphysics? After all, you would except them to be highly interested in a field of inquiry that revealed, using scientific methods, the most general or fundamental facts about reality!

This is how naturalists should title their papers

John Bickle: Real Reduction in Real Neuroscience: Metascience, Not Philosophy of Science (and Certainly Not Metaphysics!), 2008


The problem with Bickle, however, is that his brand of "metascience", judging from what I have read from him, is still too close to mainstream philosophy of science, and therefore not naturalistic enough.

Can verificationism itself be verified?

That is a silly question, and a negative answer can't be used to "refute" verificationism. Ladyman and Ross:

"our verificationism isn't supposed to itself be something established as true. It's just a stance that seems very sensible because if you don't adopt it you can conjecture worlds without limit and indulge in analytic metaphysics that will appear useless to everyone else." (Protecting Rainforest Realism, 2010)

Utter significant truths, or your life is a sad waste

A fantastic quote from Philip Kitcher:

"Your duty isn't just to utter truth, but to utter significant truth. ... Imagine Humpty, a self-styled dedicated inquirer. Humpty spends his life piling up truth, and he does it through intense acts of postulation. His rate of postulation is so fast that his notebooks are constantly filling up with the vast numbers of new truths he has discovered. Eventually, after his long career is over, the archivists come to prepare the Gesamtausgabe that will include all his many discoveries. I reproduce a fragment of a typical page (one drawn from random out of the hundreds of thick volumes).

   All snarks are snarks.
   All boojums are boojums.
   All snarks are boojums.
   All knurlytoodles are either snarks or boojums.
   No knurlytoodle is both a snark and a boojum.
   If there is a boojum, then the smallest knurlytoodle is one.

The marginal notes record the postulations that show all these fascinating claims to be analytic truths.

Is Humpty a responsible inquirer? ... His pages contain nothing but truth, and his careful postulations reveal his justifications. So perhaps we should celebrate Humpty? I think not. His archive is a travesty of inquiry, his life a sad waste. There is nothing to learn from him." (Some Answers, Admissions, and Explanations, in Marie I. Kaiser, Ansgar Seide, eds. Philip Kitcher: Pragmatic Naturalism, 2013)

Are philosophical truths worth knowing?

If philosophers, in some distant future, manage to find out some philosophical truths (don't hold your breath), would those truths be even worth knowing? I highly doubt it.
Paul Horwich has pointed out what he takes to be a questionable feature of theoretical or traditional philosophy:

"its presupposition that true philosophical theories are worth knowing. The grounds for scepticism on this point are that none of the explanations of the objective value of true belief available elsewhere appears to carry over to philosophy." (Wittgenstein's Metaphilosophy, 2013)

Most people would probably agree that philosophy doesn't give us practical benefits. But what about the value of 'sheer understanding'? According to Horwich, there is no such understanding to be found in the realm of traditional philosophy:

"in the a priori domain we cannot reasonably deploy the picture of increasingly profound layers of reality - the lower-level facts explaining the higher-level ones. Thus we do not have genuine explanatory depth in philosophy. So it is hard to see what sort of 'understanding' its theories could conceivably provide." (ibid.)

Horwich is right. It is likely that philosophy does not provide anything of value, not even for those who pursue sheer understanding or knowledge for knowledge's sake.

What is left for philosophers to do?

Answer: science.

"if many philosophers, remaining in a distinctive institutional niche, were to take up naturalized metaphysics as we Ladyman & Ross characterize it, they may end up doing a mix of mathematics and computer science, closely informed by discoveries from fundamental physics and motivated by target problems in the special sciences." (Don Ross: Will scientific philosophy still be philosophy? 2013)

"From our perspective, epistemology begins with a branch of cognitive science that investigates good reasoning. It includes work in psychology, statistics, machine learning, and Artificial Intelligence." (Michael A. Bishop and J. D. Trout: Epistemology and the Psychology of Human Judgment, 2005)

Bishop and Trout of course think that epistemology should be a branch of philosophy of science. I have never understood this part of their naturalism. If we are going to be naturalists, as I think we should, why not settle for science? Why would we need idle philosophy of science in addition to science?

What metaphilosophical naturalism means

Metaphilosophical naturalism = scientism = verificationism.

Here are some of the best statements of naturalism I have ever read in the philosophical literature:

"there is no such as a justifiable purely philosophical conclusion about any empirical phenomenon (and there are no such things as "non-empirical phenomena"). Therefore, anyone who wants to defend a philosophical thesis had better be prepared to defend it as, in large part, a scientific proposition based on scientific evidence. ... one should try to make the science in question independently interesting as science, even (indeed, escpecially) to people whose tastes don't run to philosophy." (Don Ross et al: Midbrain Mutiny, 2008)

"It is the mission of scientific institutions to strive to provide a complete objective account of the universe at all scales of description. This ambition can never be realized, but that is only because scientists will never be able to make every possible observation or take every possible measurement - not because there is a rival path to knowledge, such as religion or intuitive insight, that performs better in some domains of inquiry." (Don Ross: Philosophy of Economics, 2014)

"Since science just is our set of institutional error filters for the job of discovering the objective character of the world - that and no more but also that and no less - science respects no domain restrictions and will admit no epistemological rivals (such as natural theology or purely speculative metaphysics). With respect to anything that is a putative fact about the world, scientific institutional processes are absolutely and exclusively authoritative.

... 

no hypothesis that the approximately consensual current scientific picture declares to be beyond our capacity to investigate should be taken seriously.

... 

naturalism and verificationism are the same thesis, or almost the same thesis." (James Ladyman and Don Ross: Every Thing Must Go: Metaphysics Naturalized, 2007)

They are of course talking about epistemic, not semantic, verificationism. The hypotheses of analytic metaphysics are meaningful. They are just not worth investigating.
Ladyman and Ross don't say this, but a direct consequence of epistemic verificationism is that most debates that are currently going on in philosophy (i.e. Humeanism vs non-Humeanism about laws of nature) should be abandoned completely. They are not resolvable by ordinary scientific/empirical/mathematical means, and are therefore a waste of time. This is also my opinion. If you can't figure out a way to solve your question empirically or mathematically, you should abandon it, and stop wasting your funders' money.

Seriously serious metaphysics

If metaphysicians want to be taken seriously as inquirers into the nature of reality, they should be talking about quasars, quarks, black hole radiation and spontaneous symmetry breaking, instead of zombies, gunk spheres, persistence and grounding.

Of course, it is highly unlikely that metaphysicians, with their typical philosophical training, are able to add anything to our understanding of these physical entities and phenomena - or any real-world phenomenon for that matter - that scientists haven't already figured out for themselves.

Since science is our best and only way of studying objective reality, science has taken over the job of metaphysics. Science - and only science, not philosophy of science - tells us what exists, what is the nature of that which exists, and what reduces to what.


I like James Woodward's distinction between "ontology1" and "ontology2":

"in some areas of science, 'ontology' simply refers to what are taken to be the most basic entities or properties or structures in some area of inquiry or to the most useful or perspicuous way of classifying or conceptualizing these. ... Let us call this ontology1. It is ontology in the sense of ontology1 that geneticists have in mind when they speak of constructing a "gene ontology" or that cognitive neuroscientists have in mind when they speak of the importance of constructing a "cognitive ontology". ... On this understanding, constructing an "ontology" (that is, an ontology1) is a matter of ordinary empirical or scientific investigation" (Methodology, ontology, and interventionism, 2014)

By ontology2 he refers to the way mainstream metaphysicians do ontology:

"For example, ontologists2 often focus on questions like the following: what are the 'truth-makers' or 'grounds' for causal claims (laws of nature?, powers and dispositions?, relations of necessitation between universals?)" (ibid.)

In my opinion, serious metaphysicians (seriously serious, not "serious" in the sense of Frank Jackson or David Armstrong), when doing ontology, should do nothing but ontology1.

The naturalist as a night watchman

If radical metaphilosophical naturalism (scientism, basically) is true or, if we do not want to use the word "true", the most reasonable policy or stance to take, then doesn't that mean that philosophers should just quit their jobs since there would be nothing left for them to do? Not necessarily. It could be that naturalistic philosophy, consisting mostly of criticism instead of positive contributions to philosophy, is needed to keep people on guard against non-naturalistic philosophy (that is, almost all research that is being done in philosophy departments).

Here is a quote from Ernest Gellner. He talks about linguistic philosophy, but it could be applied just as well in the context of naturalism:

"The theory of philosophy runs: past philosophy has been mainly abuse of language, future good philosophy will be the diagnosis and elimination of such abuse. (It is admitted that some past philosophers did good work without understanding what they were doing.) This lends itself to various conceptions of the good work left for philosophers to do in the future: Euthanasia of philosophy. Or autopsy. Or endlessly protracted prophylaxis. Or others still, including l'art pour l'art.

These possibilities must be explained more fully:

Linguistic Philosophy can conceive of its own activities as the euthanasia of philosophy. There is, in its view, no room on the map of knowledge for the kind of special insights that past philosophy claimed, or indeed for the kind of special, strange questions with which it was preoccupied. But those alleged questions and putative insights are not to be simply outlawed, but gently, so to speak comprehendingly, eliminated. Only such understanding, "therapeutic" elimination is truly effective, and as a by-product of it we get some understanding of how we use language. Simple proscription was ineffective.

The question arises whether there is not a danger that, the euthanasia being completed, the linguistic philosopher may find himself out of a job. This disagreeable possibility is countered in a number of ways:

Linguistic Philosophy is conceived not merely as a therapy or euthanasia, but also as prophylaxis, and as a prophylaxis against a necessarily ever-present danger. The disease it wards off is inherent in language: all language users will ever be tempted to misinterpret the various uses of their language in terms of each other. . . . This is the Night Watchman theory of philosophy: it has no positive contribution of its own to make, but must ever be on guard against possible abuses that would interfere with, confuse, genuine knowledge." (Words and Things, 1959)

A puzzle about naturalists: they do not do science

Metaphilosophical naturalists think that philosophers should rely on the methods and results of science, implying that philosophers should just start doing science. Why do so many of them then keep doing philosophy instead of science? Why didn’t Quine, for example, become a psychologist after writing his paper Epistemology Naturalized?

Some naturalists may switch to philosophy of science from analytic metaphysics or epistemology, but what they usually end up doing is still philosophy, not science done with rigorous empirical methods.

O. K. Bouwsma pointed out this puzzle already in 1965:

"These sentences are strictly an enunciation of policy. In effect they say: "Let us be scientific." And negatively: "No more metaphysics." In a sober and quiet way a naturalist might say: "I've tried to do metaphysics. I can't grasp it. So I've turned to matters within my reach and grasp. I can do botany so much better. Or I can cut hair or polish teeth." If this were now what naturalists did, there would, I think, be no mystery at all. What causes the difficulty is that having said: "We are going to do science," they do not do science. If a man who sold groceries suddenly tired of selling groceries, exclaimed: "Enough! I am going to wash automobiles," and went out and washed automobiles, there would be no puzzle about this. But if he repeated his resolution frequently, put on his hat and coat and walked to the door, and then started for the other side of the store to sort potatoes, what then?" Well, so it is." (Philosophical Essays)

Analytic epistemologists, please turn your jobs over to psychologists!

Epistemology and the Psychology of Human Judgment by Michael A. Bishop and J. D. Trout (2005) is my favorite book about epistemology. Here are some nice quotes:

"When we began to study epistemology in graduate school, it seemed so full of promise. Who wouldn't want to divine the structure of knowledge? But somewhere around the third epicycle on a counterexample involving reliable clairvoyants, back-up electrical generators, or an environment full of objects that are phenomenologically identical but ontologically distinct, SAE [Standard Analytic Epistemology] jumped the shark."

"the main problem with SAE is methodological: its goals and methods are beyond repair."

"In the natural sciences ... hypotheses are typically tested against the world. But in SAE, hypotheses are tested against the well-considered judgments of other (similarly trained) philosophers."

"SAE rejects various accounts solely on the grounds that they violate these judgments. ... If physics had been burdened with such a conservative method, we wouldn't have relativity, quantum mechanics (or perhaps even Copernicanism!)." 

"This is a thoroughly descriptive endeavor." 

"SAE is actually an odd kind of cultural anthropology: building theories that describe how privileged (mostly) Westerners with Ph.D.s in Philosophy engage in epistemic assessment. ... If SAE is but anthropology, it is unclear on what grounds its proponents can reasonably make universal normative claims about the nature, origin, and limits of human knowledge." 

"Insofar as the core of the theories of SAE is descriptive, they are very likely to be bad descriptive theories." 

"If philosophers want an account that mimics their epistemological judgments, all we would need is a psychologist who is willing to model our judgments ... . Indeed, if philosophers really want to begin their epistemological musings with a descriptive core that accurately accounts for their judgments about knowledge or justification, they would save a lot of time, energy, and expense by employing a few psychology graduate students." 

"It doesn't matter how deeply philosophers may have considered and refined their epistemic judgments. We still need to know what's so great about philosophers' considered epistemic judgments."

The scrap-heap of misguided effort

I have never understood why some people who don't like analytic metaphysics still accept analytic epistemology. I do not see much qualitative difference between them (and please do not say that analytic epistemology gets to stay because it is somehow "normative").

"When we throw analytic metaphysics on the scrap-heap of misguided effort, most of analytic epistemology goes with it." (Don Ross: Will scientific philosophy still be philosophy? 2013)

"Much of our critique of the role of intuitions in metaphysics applies to other areas of philosophy. Weatherson (2003) argues against the weight that has been given to intuitions in epistemology post-Gettier. He defends the traditional conceptual analysis of knowledge against Gettier on this basis. From our perspective, the role of intuitions in that analysis is just as suspect as their role in undermining it." (James Ladyman and Don Ross: Every Thing Must Go: Metaphysics Naturalized, 2007)

Contemporary metaphysics is frivolous (tip: hide it from the scientists)

I think the problem with philosophy-bashing physicists, such as Lawrence Krauss, Stephen Hawking and Neil deGrasse Tyson, is that they are way too nice. Why are they so nice? Because they probably do not read much academic philosophy. If they knew how bad the situation really is in philosophy, they would be even more rude.

"Leaf through a handful of recent works in metaphysics and you will soon find yourself on trips to possible worlds populated by zombies, disembodied spirits, unicorns, dragons, trout-turkeys, writer-cucumbers, gunk spheres, and - in a chummy in-joke - the mereological fusion of David Lewis and a talking donkey. Even the most unrepentant of analytic metaphysicians should be willing to concede that it at least looks bad that such paraphernalia is the stock-in-trade of today's metaphysicians, given their pretensions to be engaged in a noble intellectual pursuit.

... 

the idea that a gunk-sphere or a zombie is somehow very much a 'real' possibility does essential work in the arguments in which they are cited, since their very possibility is often taken to refute a rival thesis. As such, taking these preposterous entities ontologically seriously is crucial in the analytic context, and the seriousness that we feel able to impart to metaphysics correspondingly diminished." (Steven French and Kerry McKenzie, Rethinking Outside the Toolbox)

Scientists are naive in the sense that they interpret philosophers too charitably. They do not realize how silly almost all of academic philosophy really is. Listen to Daniel Dennett:

"[Some scientists] have thought that when philosophers were comparing zombies with conscious people, they were noting the importance of emotional state, or neuromodulator imbalance. I have spent more time than I would like explaining to various scientists that their controversies and the philosophers' controversies are not translations of each other as they had thought but false friends, mutually irrelevant to each other. The principle of charity continues to bedevil the issue, however, and many scientists generously persist in refusing to believe that philosophers can be making a fuss about such a narrow and fantastical division of opinion." (Sweet Dreams, 2005)

Should analytic metaphysics be discontinued?

Yes, because it fails in its goal to discover facts about the nature of reality.

"almost all claims by analytic metaphysicians that are not anodyne are refuted by contemporary fundamental physics."(Don Ross: Will scientific philosophy still be philosophy? 2013)

Every Thing Must Go: Metaphysics Naturalized by Ladyman and Ross (2007) has already become a classic. The book is filled with juicy quotes. Although their positive view, information-theoretic structural realism, is still too philosophical to my taste, I agree wholeheartedly with what they say about analytic metaphysics:

"contemporary analytic metaphysics, a professional activity engaged in by some extremely intelligent and morally serious people, fails to qualify as part of the enlightened pursuit of objective truth, and should be discontinued."

"standard analytic metaphysics (or 'neo-scholastic' metaphysics as we call it) contributes nothing to human knowledge"

"a group of highly trained professionals have been wasting their talents - and, worse, sowing systematic confusion about the nature of the world, and how to find out about it"

"metaphysicians have constructed a hermitically sealed world in which they can autonomously study their own special subject matter."

"No scientist has any reason to be interested in most of the conversation that now goes on under the rubric of metaphysics."

"Mathematics and science have undoubtedly borne fruits of great value; a priori metaphysics has achieved nothing remotely comparable, if it has achieved anything at all."

"There are three ways in which analytic metaphysicians who rhetorically emulate science sometimes or often fail to follow through their naturalistic pretence: 

(1) They ignore science even though it seems to be relevant. 

(2) They use outdated or domesticated science rather than our best contemporary science. 

(3) They take themselves to be able to proceed a priori in the investigation of matters upon which they claim science does not bear."

"for neo-scholastic metaphysicians intuitive judgments are typically all that ever passes for evidence."

"We think that such people are indeed doing nothing but revealing properties of themselves and don't usually realize it."

So what if anti-philosophy is also philosophy?

Whenever somebody makes critical remarks about philosophy, the defender of philosophy screams 'but that is also philosophy!' as if criticism of philosophy is somehow necessarily incoherent. Here is Peter van Inwagen's expression of the idea:

"The fate of logical positivism is the fate of all attempts to diagnose the failure of philosophy to produce a body of established fact or even a body of provisionally accepted theory. Such diagnoses are invariably "just more philosophy" and exhibit the very symptoms they are supposed to explain: they are proposed, people argue about them, a few converts are made but only a few, and, in the end, they retire to occupy a Place in the history of philosophy." (Metaphysics, 2014)

Well, so what? Jason Brennan puts it well:

"'Philosophy is irrational' is a philosophical position. If philosophy is irrational, so is the view that philosophy is irrational. If philosophical argumentation never establishes any position, then the anti-philosophy position cannot be justified by philosophical argumentation. The Argument against Philosophy refutes the Argument against Philosophy. Even if this defence works, it is embarrassing if this is the best defence philosophy has. Yet, it is not obvious that the defence succeeds. It may just be that all philosophy is unreliable except anti-philosophy philosophy." (Scepticism about Philosophy, 2010)