The Legend
Once upon a time, there was a cognitive neuroscientist named Hermann.
Like his colleagues, Hermann read articles, applied for funding, and was
a proficient neuroimager. He taught classes and went to department
meetings. But unlike his colleagues, Hermann harbored a dark secret. It
was a secret blacker than the coffee he drank while explaining the Libet
studies to his undergrads for the fiftieth time. He dared not reveal the
secret to anyone, even on his many fake Twitter accounts, lest the
information somehow be traced back to him: Hermann was a Kantian.
Graduate school had been difficult for Hermann. A convert to
transcendental philosophy at age 17, he didn’t share his classmates’
enthusiasm for cutting-edge theories of mental processes. He just
couldn’t see the point of devising or testing newfangled psychological
concepts like “attentional control” and “reward-prediction error”. After
all, hadn’t Kant already outlined the true psychology back in
the 1780s? What more could the world want?
But nearly failing his first psychology courses taught Hermann never
to disclose his true convictions, and so he dutifully read his textbooks
and reproduced the “correct” answers on tests. He asked questions at
department talks to throw his supervisors off the trail. He gave papers
on his lab’s work at the APA and SPSP. Those results led to a
dissertation on neuroeconomics, which he resented while writing and
loathed after it got him a social neuroscience postdoc. Yet once again
he did what he was supposed to, and scanned countless fMRI subjects
while they watched videos of people talking and laughing. He always
wrote his findings up on time and sent papers to well-targeted journals.
Many were accepted, some even at prestigious venues.
In reality, though, Hermann was just biding his time. All through
graduate school and his postdoc, Hermann pretended to believe in the
constructs of contemporary psychology, but deep down, he was just
waiting for the moment when he could follow his heart. At last, the
years of hypocrisy and dissimulation paid off: his postdoc papers struck
a chord with the right committees, his job talk had the perfect jokes
(“Based on the work of my very warlike colleague, Sarah Bellum, we…”),
and he dazzled the right group of faculty. Hermann landed two big grants
and a tenure-track job. To celebrate he took a long walk down the lane
near his house at precisely 3:30 pm. On the walk he contemplated his
future and looked at sticks; he knew the real work was just
beginning.
The next morning Hermann gathered his notes from countless magical
nights with Immanuel and got his real research program underway. His
goal was simple: find the neural correlates for all the major constructs
in Kant’s psychology. With his detailed knowledge of the first
Critique and other texts, Hermann knew that his work would not
involve conceptual difficulties. Methodology wasn’t a problem either,
since his grad-school education was more than sufficient. He was merely
doing what every other cognitive neuroscientist did—he just happened to
be doing it within a Kantian framework.
It was not hard to find the neural correlates for the faculty of
judgment, for example. While inside the fMRI scanner, his subjects read
and reflected on propositions. Hermann carefully counterbalanced the
stimuli to control for effects like variable propositional content and
emotional valence. To the surprise of no one, his statistical analyses
showed that certain brain areas activated during the tasks. These
crucial areas showed regular patterns both across subjects and across
studies. In this way, he identified not only the cortical regions
engaged in acts of judgment, but also the sub-regions which process the
various logical forms of judgments. He connected judgments of quality to
one area and judgments of relation to another, and judgments of quantity
and modality to interconnected networks.
Hermann made similar discoveries about spatial representations,
thereby illuminating the neural mechanisms of “the form of all
appearances of outer sense.” (Kant 1998, A26/B42) His work produced
the first map of the Kantian cortex.
No, day-to-day research was not the hard part. The real problem was
time. For his arguments to be persuasive, Hermann knew that he needed a
lot of data, and needed the computing cluster to analyze it with fancy
statistics. But he also knew that he couldn’t let anyone find out what
he was doing. So he stonewalled his colleagues when they asked about his
results; he ignored emails from his department chair; he kept his
unfortunate non-Kantian graduate students in the dark about the true
import of their work. The tipping point came at his third-year tenure
review. The neuroscience faculty was ready to give him marks for
unsatisfactory progress, which would have been grounds for dismissal,
but a letter of recommendation from Hermann’s postdoc director saved the
day. Her letter assured department members of Hermann’s potential,
promised that he would revolutionize the field, and urged them to retain
him. Hermann barely survived the vote. He knew he needed to hurry—he had
less than three years to go.
In the darkest times, when he doubted his life’s work and his goal
appeared most distant, Hermann comforted himself by reading what Kant
once wrote to Samuel Thomas Soemmering. In a 1795 letter, Kant spoke to
the anatomist Soemmering about the sense organs in the brain. Sensory
representations had to be combined, Kant said, and it was incumbent on
natural philosophers to “render that unity comprehensible by reference
to the structure of the brain.”(Kant 1999, 501) Hermann drew strength
from his forebear’s prescient understanding of his own research program,
as he attempted to show the neural correlates for a priori
contributions to cognition. Hermann also knew he carried on Soemmering’s
physiological work, to which Kant gave effusive praise, by finding the
chemical mechanisms of the mental faculties.
But the next three years passed, and since he released his results
only in controlled trickles, Hermann simply did not publish enough to
get tenure. It was understood in his department that he would have to
leave after his seventh year. Then, at the start of that year, a miracle
happened: stacks of finished manuscripts, all on the cognitive
neuroscience of Kant’s transcendental philosophy, appeared on the
department chair’s desk. All together, the manuscripts told a
magnificent story of how the brain realized the posits of Kant’s
psychological theory. Early papers laid the groundwork by finding brain
areas for the most fundamental concepts, like the faculty of judgment,
the forms of space and time, and the transcendental unity of
apperception. Later work described connections among these concepts that
even Kant had not noticed. Shorter papers filled in smaller details, and
a single flagship paper—Hermann hoped to send it to
Neuron—assembled the main results into a new, elegant, and
powerful theory of the mind and brain. Always and everywhere, Hermann’s
results met and even exceeded accepted standards of experimental rigor
and statistical significance.
At first, the chair was laughing as he leafed through the pile,
imagining the pleasure he would feel at firing this Prussian charlatan.
But the laughing stopped as he began to see the depth, creativity, and
penetrating intuition with which Hermann had carried out his work. He
convened a special faculty meeting to discuss the matter. On the one
hand, Hermann had published nothing of note during his six years as
assistant professor; on the other, he was now sitting on dozens of bold
papers, each ready to submit. The chair asked the faculty for their
opinions. “It’s such a waste!” a recently-tenured associate professor
yelled. “Seven years down the drain! This whole thing is a travesty, and
a sham, and a mockery! I won’t stand for it!” Many others agreed. But
Hermann had his defenders, mostly among the older faculty. These full
professors, now in the twilight of their careers, had seen countless
psychological theories come and go. From their point of view, the
conceptual framework of Hermann’s research did not differ essentially
from so many failed frameworks of the past.
In the end, Hermann’s colleagues decided to give him a choice: he
could either leave the university or back up his neuroscientific results
with behavioral studies. The faculty supporting him were worried that
Kant’s view was too procrustean to be plausible in the modern age. They
wanted to see behavioral results demonstrating that Kantian psychology
could account for known complexities of human action. They did not think
it could be done, but if Hermann were able to pull it off, they thought,
they could not justify forcing him out.
Hermann felt he couldn’t abandon his work now—not when he had come so
far. So he designed an arc of behavioral studies to support Kant’s
psychology. Fortunately for him, behavioral results are faster and
cheaper to get than neuroimaging, and Hermann Turk’d almost everything.
In what became his annus mirabilis, Hermann completed his
entire suite of studies, performed some requisite follow-ups, and wrote
all his results before the end of the spring semester. He even made
original discoveries about the structure of cognition from a Kantian
perspective (these he considered submitting to philosophy journals, but
seriously, what’s the point?). Once again, the chair showed up to work
one day to find another pile of papers on his desk, showing how to
implement Kantian psychology to describe all aspects of human
behavior.
He convened a second meeting, and for a second time, the question
divided the members of Hermann’s department. Some continued to think
that Kantian psychology was unworkable in principle, and that the idea
of a “Kantian cognitive neuroscience” was a farce. Others felt that
Hermann’s body of work was, in many respects, comparable to that of
other faculty that the department had tenured. But all agreed on what
Hermann had set before them: a coherent, exhaustive, and radical
alternative to the contemporary conceptual framework of cognitive
neuroscience.
The behavioral work showed Kantian psychological concepts to be much
more flexible than anyone had realized, and sufficient to account for
human perception, action, and memory. The evidence for the Kantian
constructs was every bit as relevant and rigorous as it was for anything
else in psychology. The imaging work showed, moreover, that these
concepts had clear and reliable neural correlates, and that multivariate
analyses could predict their instantiation in a wide variety of tasks.
Indeed, it was not a matter of weighing evidence at all, for the
evidence was equal on both sides—Hermann’s brain data and behavioral
studies were beyond reproach. Nor was it that Hermann had shown how to
make certain Kantian constructs work within contemporary
psychology. Rather, he was in fact offering a complete
replacement for all of contemporary psychology. This
Hermann’s colleagues understood, and it was the root of their complaint.
Hermann’s work formed a complete science of human behavior which was
fundamentally incompatible with competing approaches—that is, with
their approaches. And he did it all with a brilliance and
Teutonic flair that no one had ever noticed in him.
Department members faced a stark choice: dismiss an apparent rising
star (“einen aufgehenden Stern”, joked an older faculty member no one
liked), or tenure a Kantian. They abhorred both options. On the one
hand, they could get rid of him. But doing so would be an indictment on
their own careers, for Hermann had done everything they had, and just as
well, only with a different set of cognitive concepts. They realized
that had the history of psychology gone differently, they might have
been Kantians too. On the other hand, granting him tenure would sanction
Hermann’s revival of transcendental psychology—and let’s face it, no one
wanted that. The empirical evidence was equal on both sides, and the
practical consequences were all bad. How could they decide?
In the end, however, Hermann spared them the trouble. Having been
asked to speak in his own defense, he instead offered his resignation.
The annus mirabilis had ironed out the last wrinkle in his
work, he explained, and so he had achieved his goal. There was nothing
left for him to do. His results were just as good as theirs or anyone
else’s—he knew it, they knew it, and he knew they knew it. Hermann rose
from his chair, grabbed a few of the big cookies they always had at
faculty meetings, and walked out into the sunset. No one ever heard from
him again.
Thus the legend of Hermann, the Kantian cognitive neuroscientist, was
born.
The Moral
Hermann’s legend makes several important points about cognitive
neuroscience. I’ll elaborate on some of them here as well as on the
philosophical issues involved. I’ll also consider some objections to my
framing and conclusions.
To begin, I am not the first to tell a tale like Hermann’s. Bub (2000) gave a
version of it using phrenology, and so did Poldrack (2010).
Others have told it as well (Uttal 2001; Anderson 2015).
All these versions involve cognitive ontologies. A cognitive
ontology is the set of entities, processes, and constructs in one’s
theory of cognition. We should understand “cognition”
broadly here, as including sensation, perception, consciousness, and any
other mental process or phenomenon. So if our ability to remember a
phone number by silent rehearsal requires a “phonological loop” (Baddeley and
Hitch 1974), then the phonological loop belongs in our
cognitive ontology.
Most disputes in psychology concern the details of a cognitive
ontology: whether this or that entity belongs in it, or whether some
entity has this or that property. Memory researchers debate, for
example, whether consolidation is distinct from reconsolidation
(Alberini and
LeDoux 2013). Consolidation occurs when a memory becomes
insensitive to disruption or change. But each time someone reactivates a
memory, it becomes susceptible to interference again. Is this latter
event also just consolidation, or is it a separate process with
different temporal and mechanistic profiles (Lee, Nader and Schiller 2017)? Our
answers to these questions determine part of our cognitive ontology, and
we can ask similar questions across psychology.
In turn, most research programs in cognitive neuroscience deal with
mappings between a cognitive ontology and brain structures. The mappings
involve local questions about processes like reconsolidation, but also
global ones about which neural structure types we should map to.
Philosophical theories about mechanisms (Piccinini and
Craver 2011) and large-scale data projects (Yarkoni et al.
2011) try to solve these problems.
The workflow of a typical research program in cognitive neuroscience
begins with whatever constructs the currently accepted cognitive
ontology contains. Researchers then design tasks that they believe will
involve those constructs. Next, they have study participants perform the
tasks while some recording technique, such as fMRI or EEG, measures
their neural activity. The hope is to find activity that exceeds a
certain threshold or survives some correction for multiple comparisons.
Should they find it, researchers map the construct they started with to
the area showing the activity. They can then claim that the construct
“engages” or “recruits” neural activity in that area. If they are
careful, they will condition their claims on the tasks used, for tasks
are inescapable mediators of mappings between mind and brain.
The legend of Hermann, however, is not about projects such as these.
It is not about local disputes in psychology, nor the details of some
mind-brain mapping. Rather, it is about which cognitive ontology we
should prefer at the general level. It questions why a research
program in neuroscience should begin with constructs from the received
ontology of contemporary psychology at all. Why not select from an
altogether different cognitive ontology? The history of psychology
offers many choices. Hermann’s tenure case also raises the possibility
of the wholesale replacement of one cognitive ontology by
another, where the replacing set of concepts is different from and even
incompatible with the one replaced.
In short, the primary point behind Hermann’s legend concerns what I
call the fundamental problem of cognitive ontologies. Most
studies in psychology don’t touch this problem, for they work within an
accepted ontology in order to refine it or fill in the details. The
fundamental problem of cognitive ontologies is whether we should
actually accept the received ontology, or prefer some other. Sure, a
budding psychologist has practical reasons to reject Franz Joseph Gall’s
phrenological concepts as she begins her career. Chief among them is
that she’ll never get a job by studying things like “veneration” or
“amativeness”. However, her practical reasons do not solve the
in-principle problem of choosing a cognitive ontology to begin with. She
could start her research just as well with the constructs of Aristotle,
Galen, Christian Wolff, or anyone else with a theory of mind.
We can also put it this way: the fundamental problem of cognitive
ontologies is knowing whether the conceptual scheme structuring your
ontology is the right one. The problem is determining whether you have
the correct conceptual language in general, not just in
particular cases.
Kant’s psychology is one such conceptual language. So why not be like
Hermann and adopt it, instead of contemporary cognitive science, as the
scheme to structure our whole ontology? Instead of “consciousness” we
could talk about the “transcendental unity of apperception”, for
example. Kant wrote, “[t]he transcendental unity of apperception is that
unity through which all of the manifold given in an intuition is united
in a concept of the object” (Kant 1998, B139).
Assuming this is true, we can imagine various ways in which the unity
of apperception might break down. People with akinetopsia or motion
blindness do not have smooth perceptions of motion—their visual
experience of motion is frame-by-frame, as it were, with no perceived
connection between the frames. A good Kantian hypothesis would be that
akinetopsia results from failing to properly combine the sensible data
in the manifold. We could study this phenomenon in many ways: we could
get behavioral profiles of people with akinetopsia-like symptoms and
correlate our findings with life histories (Ovsiew 2014); we could test lesion
patients with similar deficits (Rizzo, Nawrot and Zihl 1995); we could
try to induce akinetopsia via transcranial magnetic stimulation and
disrupt normal apperception ourselves (Beckers and
Hömberg 1992). There would be many other avenues to explore.
Some will scoff at this suggestion, but the point is that I have just
described a research arc that would carry someone to associate professor
and beyond. The published results would look an awful lot like
psychology papers now, except Kantian concepts and a Kantian cognitive
ontology would structure them.
I could provide more examples to deepen the point, or outline fMRI
studies that Hermann could have done to plumb the implementation of
Kant’s psychology. But the actual history of psychology furnishes us
with more and more plausible examples than we could ever hope to invent.
The cycle of theory-replacement in the history of psychology is
the existence proof for an in-principle problem.
There is a temptation to believe that, because psychology is a
“science” now, its current cognitive ontology must stand on firmer
ground than past ones. Can’t we now draw sharper distinctions between
different systems of memory? Don’t we have better information about
exact temporal profiles? Aren’t we able to see better how entities in
the ontology relate to each other? Yes, psychology does all this now,
and it didn’t or even couldn’t do it in Kant’s day. But we should not
therefore infer that the accepted ontology has better epistemic
credentials. The reason that items in our cognitive ontology have those
properties is just that we now do psychology in a way that encourages us
to identify those properties. Had we been doing psychology in Germany in
1800, but with modern methods, we could have discovered the same “facts”
about the posits of Wolffian and Kantian psychology. That we could
identify those properties, however, says little about their reality.
As such, there is no doubt that a real-life Hermann would succeed in
finding neural correlates for the faculty of judgment, as described in
the legend. He would have no trouble finding consistent, statistically
significant patterns. His studies could use classic psychological
testing methods like additive factors and subtraction. These methods
work regardless of the entities in our cognitive ontology. They are
varieties of experimental and task design, and any “justification” they
confer on gathered data is irrespective of that ontology.
The problem of cognitive ontologies does not emerge because of modern
methods, though two other (independent) methodological issues exacerbate
it. The first begins in psychology: it is not difficult to find
significant results in human cognitive and behavioral testing. Human
behavior is amenable to description by many conceptual languages, which
is why the history of psychology is so rich with ideas. A part of the
problem stems from current experimental techniques, but another part is
more endemic to psychological practice (Meehl 1967). The second methodological
problem comes from neuroscience. Brains will show neural activations to
anything and everything, so the fact that we have found an activation is
not in itself very remarkable. We couldn’t not have found an
activation.
I will say a bit more about these two problems below, but they are
not my primary concern. The legend of Hermann itself just illustrates
the fundamental problem of cognitive ontologies and some associated
philosophical issues. What, then, should we do about it?
Given the nature of psychology, I think the right move is to be
instrumentalist about psychological theories. Earlier I spoke about the
“right” ontology, and finding the “correct” conceptual language. Human
behavior and its neural basis may not be the kind of phenomena that
allow true theories; it may just be that certain ontologies are better
for certain situations. We could do cognitive neuroscience with one of
many ontologies, but we pick the one that seems most useful for our
purposes, whatever those may be.
Not all practitioners of the mind-brain sciences want to go
instrumentalist, however. Other ways to respond seek to carve out more
room for realism and a “correct” ontology. Let’s look at some of
them.
Adapting Anderson’s (2015) discussion of mind-brain mappings,
we can distinguish three realist-motivated approaches to the fundamental
problem of cognitive ontologies. The first, taken by the vast majority
of psychologists and cognitive neuroscientists, is the
conservative approach (Price and
Friston 2005). This attitude assumes that the correct
conceptual scheme is probably a lot like the one we have now, and so our
cognitive ontology only requires local tweaking. The second approach is
moderate. It attempts to let the brain decide which of two
cognitive constructs is better. The third is the radical
approach. It suggests a re-thinking of “the very foundations of
psychology in light of evidence from neuroscience and evolutionary
biology” (Anderson 2015,
70).
None of these three approaches to the challenge of cognitive
ontologies necessitates realist commitments, though all three trend in
that direction. All three suggest that there is a “true” ontology and
that either we’ve already found most of it, or we at least know the way
to get there. I’ll discuss each approach in more detail below, and then
explain why I don’t find them very promising.
The first approach is conservative. It suggests that we already have
most of the pieces for a true cognitive ontology—they’re just the
constructs of contemporary psychology. This approach takes the apparent
success of psychological science as evidence of the truth of its claims,
and since those claims involve elements in an ontology, the elements
must therefore exist.
The problem with the conservative response is that it begs the
question against someone like Hermann. Hermann suggests replacing the
current ontology with another one; to say we can’t do that, because the
one we have now is true, assumes what Hermann denies.
It’s also wrong to think that the “success” of psychological science,
or the fact that each published paper finds an effect, creates a problem
for Hermann’s Kantian view. Citing particular successful studies or even
batches of them does not support conservatism. This is because the
evidence for this or that current psychological theory is not thereby
evidence for the background conceptual scheme in which those theories
are framed and tested. As noted above, psychology is such that we cannot
help but find evidence for virtually any construct we go looking for
(Meehl 1967; Open
Science Collaboration 2015). Thus finding evidence for some
process says very little about the truth of the conceptual language
describing that process. In other words, the reason we don’t have
empirical evidence for Kant’s psychology is simply that no one has
bothered to gather it yet. If a real-life Hermann ever comes around,
he’ll find all the evidence he could want, but he’d be no closer to
establishing the reality of the Kantian cognitive ontology.
The second approach to the problem of cognitive ontologies is
moderate. It uses brain data to adjudicate between competing or
incompatible psychological constructs, thus letting the brain “speak for
itself”. The brain can do this in various ways. One is when competing
cognitive categories make different predictions about their neural
correlates. We can test these predictions by measuring brain activity
during task conditions that involve the categories. Another way is
through multivariate analyses, which use patterns of neural activations
to predict cognitive constructs or representational categories of
stimuli.
The moderate approach faces several challenges. For one, while brain
data might be useful for comparisons between constructs, it cannot give
an absolute measure of a construct’s reality. This point leads to a more
serious problem, which is that even brain data cannot adjudicate between
entire conceptual schemes or whole cognitive ontologies. Indeed, the
brain is a fit counterpart for psychology: it will always give us
some evidence of whatever we test for. Bub (2000) and Poldrack (2010)
used phrenology in their version of Hermann’s tale because there is no
question that phrenologists, had they used fMRI, would have found
copious activations strongly correlated to their phrenological
categories, and strongly predictive of those categories in multivariate
studies. The same is true for Hermann’s transcendental concepts, and for
any other set of concepts we care to check: no matter what they are, we
will find some neural signature of them—but it does not follow that
they are real. Brain “data” or “evidence” usually aren’t evidence
for the reality of the mental construct being tested. This point seems
to be either ignored or misunderstood by many philosophers and
scientists.
Another way of putting the issue is to say that, while the moderate
approach wishes to let the brain speak for itself, our neural organ can
really only do so in a language that we already understand,
where “we” are the designers and interpreters of experiments. If brain
data is to shed light on human thought or behavior, we must interpret
that data using cognitive concepts. Even the simplest interpretations
therefore rely on entities in a cognitive ontology, even when those
entities appear to be mere folk-psychological categories like
perception, belief, or desire. Those basic categories also inform
experiment and task design, as researchers use folk psychology to reach
broad (albeit general) agreement on how psychological constructs, tasks,
and experimental conditions relate. That whole psychological
apparatus forms a conceptual scheme for studying the mind and brain.
But if we bring to the brain a language we already understand—a
worked-out cognitive ontology—then the moderate approach begs the
question against Hermann no less than the conservative approach does.
This criticism also applies to ontology construction if the analysis
uses previously existing cognitive constructs to structure the data;
such analyses comprise the majority of “data-driven” methods (Poldrack 2010;
Yarkoni et
al. 2011; Yeo et al. 2015; Tamar et al.
2016; Eisenberg et al. 2019; Genon et al.
2018; Bolt
et al. 2020).
The third and final approach is the radical one. My objections to the
first two approaches suggest that Hermann himself begs the question
against current cognitive science since he brought a worked-out
cognitive ontology of his own to studying the brain. But there are even
more radical approaches that try to avoid begging the question. One
example is Cisek (2019), who
synthesizes a new cognitive ontology by analyzing the evolutionary
history of simple behavioral systems. Another attempt is Pessoa, Medina and
Desfilis (2021), who reject “standard mental
terms” and instead found a new cognitive ontology with “complex,
naturalistic behaviors”.
It’s too early to know whether projects like these will succeed. If a
“true” cognitive ontology exists, these are our best bets to find it,
because they throw out our current conceptual language and start with
the evolutionary environment. There are other radical approaches that I
think we can object to, however, so I will focus on those.
Other examples of the radical approach to cognitive ontologies use
large data sets to find non-obvious dimensions or axes in brain
activations. Call this the “latent structure” strategy (Yarkoni et al.
2011). I’ll discuss the strategy a bit and then present a
problem for it, which applies in varying degrees to other radical
approaches.
The latent structure strategy uses computational techniques to find
structure in neural data. The assumption is that the data’s latent
dimensions may trace the contours of categories the brain itself uses to
organize cognition. In this approach, the brain goes beyond playing
arbiter for competing constructs to reveal a brand-new set of
categories. For example, Chen et al. (2017)
use independent component analysis (ICA) with resting-state fMRI data
from hundreds of scans to identify four previously hidden brain
networks. The authors dub them the “auditory”, “control”, “default
mode”, and “visual” networks. Biswal, Mennes and Xi-Nian Zuo (2010)
perform a similar analysis on resting state data, and Schaefer et al. (2018) use functional connectivity to
produce a new cortical parcellation.
These analyses outdo Hermann’s because they are based purely on brain
measurements. You apply a technique like ICA and a robust structure
emerges that may have been impossible to detect otherwise. Unlike every
other approach, you need not bring anything to the table other than the
data. Prior to identifying the structural contours, no part of any
background conceptual scheme plays a role. This is another radical way
of tackling the fundamental problem of cognitive ontologies, and perhaps
another hope to avoid begging the question.
The challenge for latent structure strategies is
interpreting what they find. Sure, Chen et al. (2017)
find four separable networks. But where do the “auditory”, “control”,
“default mode”, and “visual” labels come from? Why interpret the
networks with that conceptual language, instead of some other?
Now, the source for the labels is, of course, the authors’ prior
knowledge of similar networks. Chen et al. (2017)
know that, in previous studies, participants who engaged in tasks
requiring cognitive control showed activation patterns matching one of
the networks they discovered. The authors then import those labels—those
entities in the background cognitive ontology—into their own study, and
use them to interpret the data. So even though the data’s structure is
discovered ontology-free, it can only be interpreted
by some existing ontology or conceptual scheme. Just as we saw with the
moderate approach, the brain can only speak in a language we already
understand. The lesson is that big data may help introduce new neural
categories, but it doesn’t and can’t provide the psychological labels
for those categories.
Jerry Fodor and Ernie Lepore (1992, 1996) once developed a similar objection
to Paul Churchland’s semantic theory. Churchland (1989, 1998)
developed a theory of meaning in which different aspects of conceptual
content were represented by different dimensions in a high-dimensional
neuronal activation space. So, to use a simplified example, the concept
“dog” might be represented by neural activations along dimensions like
“furriness”, “barking-ness”, “four-footed”, and so on. Various ranges of
those dimensions define a high-dimensional solid that constitutes the
concept “dog”.
The crux of Fodor and Lepore’s objection is that Churchland begs the
question about the labels on the dimensions. Why does the first
dimension in the activation space represent “furriness” instead of
“barking-ness”, or something else entirely? By taking the labels for
granted, Churchland smuggles semantic terms into a theory that is
supposed to explain how there could be semantics in the first place.
Latent structure strategies make the same mistake. Why is this
particular structure the “control” network, and that structure the
“default mode” network? Labeling the networks requires interpreting the
data, but interpretation only happens through cognitive concepts we
already have. In trying to discover the brain’s categories for
cognition, we smuggle in the psychological labels, and so accomplish
nothing other than putting old wine into new bottles.
In sum, I see the fundamental problem of cognitive ontologies as
leading us toward instrumentalism about psychology. Although there are
realist-friendly responses to this problem, most of them take the items
in their cognitive ontology for granted, and we can’t yet evaluate the
ones that don’t.
The moral of Hermann’s legend is the problem I’ve been discussing,
which connects to many issues in the philosophy of mind and of various
sciences. Other than inertia and the vicissitudes of history, we have
much less reason than we like to believe to prefer current cognitive
ontologies over possible alternatives. And, as Bub (2000) notes, without some resolution for
this problem,
[we cannot] differentiate what is currently undertaken [in cognitive
neuroscience] from a pointless activity in which inevitable differences
between experimental and baseline conditions are falsely attributed
specific cognitive interpretations that do not in fact correspond to
reality (Bub 2000,
470).
I conclude by considering some objections to my arguments and the way
I’ve set them up. First, you might say that this is all just a problem
of reverse inference. Suppose my neuroimaging study discovers activation
in brain area \(X\). From previous
studies, I know that \(X\) is
associated with emotion, and so I infer that my subjects used emotional
processing in my task, even though the task didn’t explicitly involve
emotion. This pattern of reasoning is called a reverse inference (Poldrack
2006). Reverse inferences require caution because area \(X\) could be involved in many other
cognitive processes, not just emotion.
The problem of cognitive ontologies is not one of reverse inference,
however. Reverse inferences have to do with evidence, and gathering more
evidence alone does nothing to solve the problem. We have an enormous
amount of papers published in cognitive psychology, but the sheer number
does not resolve the in-principle problem of ontology selection.
A second objection could be that we could solve the problem with
multivariate analyses in neuroscience. Both philosophers and
neuroscientists sometimes believe that multivariate pattern analysis
(MVPA), representational similarity analysis (RSA), and other
multivariate techniques yield some special insight into brain function
that ordinary univariate imaging analyses cannot (Nathan and
Del Pinal 2017). I am skeptical of that view, but even if it
were true, it would be irrelevant to my arguments. The problem of
cognitive ontologies is not a methodological one—at least, not one
internal to psychology or cognitive neuroscience as they are currently
constituted. As I said above, certain methodological issues do
exacerbate the problem, such as the ease with which we find publishable
results in the mind-brain sciences. But it is not the current methods of
psychology and cognitive neuroscience that give rise to the problem. It
goes beyond the conceptual boundaries of either field and so we cannot
solve it with more sophisticated statistics.
Someone might also object that the problem of cognitive ontologies is
really an issue of underdetermination of theory by data (Aktunc
2021). According to this objection, alternative ontologies
only look like live options because we don’t yet have enough evidence
for our current one. But this objection also says that psychological
theories are theories, and as such, they will always go beyond
the data. Every theory in every science outstrips the available
observations, and it’s unfair to expect a cognitive ontology to be an
exception. This objection can therefore say that the problem of
cognitive ontologies is not an issue of principle; it’s just the
expected result of humans doing psychological science.
This objection is a sophisticated one. To lay out and respond to all
the issues involved would take another paper. Here I will just give some
reasons to think that the problem of cognitive ontologies goes beyond
the underdetermination of theory by data.
As we’ve seen, Hermann wasn’t going to convince anyone of Kant’s
psychology, no matter how much his evidence “determined” his theory.
While Hermann’s work isn’t real, the cycle of theory replacement in the
history of psychology is, and we have no reason to think that the cycle
will stop with something like our current cognitive ontology.
Superficial similarities between psychology and other sciences, such as
that they are practiced in universities and use quantified measurements
and mathematical analyses, give the impression that psychology, like
physics or chemistry, trods a monotonic path up the mountain of truth.
But those similarities belie deep conceptual and interpretational
problems which may be inevitable not only in psychology but also in the
phenomena it studies.
In describing human behavior and mentality, we face a situation in
which many distinct but mutually incompatible conceptual schemes could
do the job. It isn’t just the history of psychology that shows this;
current cross-cultural psychology does too. Take “indigenous” or “local”
psychological theories, which describe human thought and behavior in
specific cultural contexts (Allwood and
Berry 2006). Rather than fitting received psychological
categories to non-Western peoples, indigenous psychologies develop new
categories tailored to their environment. Inputs to this development
include literature, observations of behavior, self-reports, and past
scientific evidence (Cheung et al. 1996). The results are
psychological theories that may account for patterns of thought and
behavior better than traditional (Western) theories.
One of the most empirically successful indigenous psychologies is the
Chinese Personality Assessment Inventory, now known as the
Cross-cultural Personality Assessment Inventory (CPAI). In addition to
categories from the standard five-factor personality model, the CPAI
includes psychological constructs like “Harmony”, “Ren Qing”
(relationship orientation), “Ah-Q Mentality” (defensiveness), and “Face”
(Cheung et al.
2001). These constructs constitute a personality factor,
“Interpersonal Relatedness”, which is not reducible to other personality
theories (Cheung et al.
2003).
If “Interpersonal Relatedness” and associated constructs like “Ren
Qing” and “Ah-Q Mentality” are incompatible with other psychological
theories, then what do we say about the state of the science?
Underdetermination suggests that we’re just lacking the evidence to
decide between them, whether or not psychology is capable of providing
it. But it’s not a leap to think there may be some real indeterminacy
here, and that there simply is no fact about whether “Ren Qing” is real.
We can study it, we can use it, and we can endorse it, but we don’t need
to conclude it must exist.
There are indefinitely many conceptual schemes for psychology,
limited only by our imagination. Whatever they are like, the brain will
oblige with consistent profiles of activation. If the data
underdetermines all the available theories to the same degree, then
maybe the problem lies not in our ability to gather evidence but in the
Dinge an sich.
One final objection. In a “no-miracles” spirit, one may say that our
current ontology can’t be that wrong, since psychology and
neuroscience are so successful. To those with the courage to make this
response: I envy your faith, but see no reason to share it.