I think a more robust defense of non-reductionism can be made in terms of the mechanisms of meaning.
I'd agree with that assessment. Various computational models of vision grow more and more sophisticated, such that it's arguable a computer system that sees a face does so by recognizing colors, contours, shading, and so on. That is, an electromechanical system that converts wavelengths to integers that stand for RGB in some way begins to mimic how we see red, green, and blue; or straight lines and curves by interpreting a CCD's state much like the state of a retina is observed. For meaning, despite that we can locate difficulties in the application of semantic function to Wernicke's area when particular types of aphasia are observed, meaning in the brain as a whole is far less understood than visual processing.
The purpose of this thread is not so much to debate the pros and cons of this argument, as to find out whether it is a recognised line of argument in philosophy of mind and whether there are philosophers who pursue something like this line of argument.
I think the basic, intuitive argument implicit in any philosophical position that embraces mind-body duality as fundamentally irreconcilable in the form:
Mind is mental, body is physical, they're exclusive, and all meaning is mental, therefore nothing in meaning can be reduced to the physical. These sorts of philosophical arguments might be considered folk philosophical arguments against reductionism that are rooted in psychological intuitive dualism. Take for instance the comment:
Um... Mind cannot be matter because mind does mind stuff that isn't matter. OK. Maple syrup cannot be matter because maple syrup tastes good and taste isn't matter. – Boba Fit
This is essentially the intuitional approach for resisting mind can be reduced to matter, and there's scientific evidence this is the norm in conceptual development. Consider from "Developmental and Cross-Cultural Evidence for Intuitive Dualism" by Chudek et al.:
Adult humans behave in peculiarly "dualist" ways. Adults everywhere profess beliefs in souls and the afterlife (Atran & Norenzayan, 2004; Boyer, 2001), mindless bodies (zombies), bodiless minds (ghosts, spirits) and minds entering new bodies (Cohen, 2007; Cohen & Barrett, 2008) and place unusual value on "genuine" artifacts (Bloom, 2005) as though they'd become infused with their owners' non-physical essence. Even medical professionals show reasoning biases when thinking about 'psychological' versus 'physical' disorders(Ahn et al., 2009). Cross-cultural research suggests that adults' intuitions about disembodied minds are strikingly similar across societies (Cohen et al., 2011). Young children sometimes expect minds to persist after their body dies (Astuti & Harris, 2008; Bering & Bjorklund, 2004). Both children (Notaro et al., 2001; Schulz et al., 2007) and adults (Ahn et al., 2009) struggle to draw causal connections between mind- and body-related phenomena. Recent cognitive-historical work even indicates dualist thinking in ancient Chinese texts (Slingerland & Chudek, 2011).
But they also say:
Alternatively, dualism may be learned gradually by participation in cultures with a Cartesian intellectual tradition.
So, the reason that Descartes was the target of Ryle's label as categorical error maker is that there are plenty of anti-reductionist arguments starting with and since Cartesianism.
Currently, the debate over the possibility of AGI can be seen as an extension of this divide between irreconcilable dualism and the belief that meaning is inherently a physical process of association of some sort. Hoffstadter and Sander explore the topic in Surfaces and Essences: Analogy as the Fire and Fuel of Thinking. While some objections to mapping mind to gray matter take the form of multiple realizability (SEP) as an objection which attacks reduction by looking at the relationship between how mental states might reduce to physical systems, others make an argument from the other direction: the physical systems we build fail to create mental states or possess meaning. Thus, narrow-AI is held up as an example that our most sophisticated attempts to create minds fall spectacularly short of modeling mind and meaning, and that semantic hallucinations by LLMs such as ChatGPT show that there is something quintessentially missing. Of course, the most famous philosophical argument of this sort is Searle's Chinese Room argument:
The Chinese Room Argument holds that a digital computer executing a program cannot have a "mind", "understanding", or "consciousness",[a] regardless of how intelligently or human-like the program may make the computer behave.
Thus, the question of how meaning and physical matter relate is very much a real-time argument undergoing testing and argumentation in experimental philosophy (SEP). The two sides essentially are trying from the bottom-up to reason to the best conclusion with people settling in two camps, the orthodox made famous by Hubert Dreyfus who became famous by point out what computers can't do largely because they don't understand, and the heterodox which is a rag-tag band of academic dreamers like the original optimistic AI folks, and current self-proclaimed AGI folks who believe that meaning can be built into systems one learning algorithm at a time.
Currently, one group of thinkers working on this problem are 2nd generation cogntive scientists with a philosophical bent like Nicholas Shea who are trying to show connections between physical systems and representations. If the representations have a physical basis, then by the representational theory of consciousness (SEP), the problem offered by intentionality is resolved by reducing intentionality to representations and showing how representations give rise to consciousness. To wit:
The idea of representation has been central in discussions of intentionality for many years. But only more recently has it begun playing a wider role in the philosophy of mind, particularly in theories of consciousness. Indeed, there are now multiple representational theories of consciousness, corresponding to different uses of the term “conscious,” each attempting to explain the corresponding phenomenon in terms of representation. More cautiously, each theory attempts to explain its target phenomenon in terms of intentionality, and assumes that intentionality is representation.
Where does meaning fit into this? Well, if meaning is primarily an association between representations (for instance as posited by cognitive semantics and conceptual metaphor which views meaning as being derived from source-target domains of neural computations), then there are physical computational mechanisms that can be shown to underlie the mental faculty of reasoning. This is why 2nd generation cognitive scientists offer mathematical models of neural computation and look to the neuroscience of consciousness (SEP) for inspiration. Unlike LLMs, the goal is to produce connectionist systems (like those proposed years ago by Rumelhart, McClelland, et al. in PDP vols. 1&2) that manifest behavior that might be considered purposeful and meaningful.
Philosophically speaking, there are still many open questions in the philosophy of language and semantics itself and a bewildering array of models and viewpoints. WP has half a dozen theories of semantics listed, and many of these aren't known in the wider philosophical communities, but are of interest to philosophers of language with a particularly strong knowledge of linguistics. Szabo and Thomason in their Philosophy of Language (GB) represent semantics as a field rife with philosophical questions and pose a number of questions and assertions their own from the origins and role of compositionality in language function to how indexicals relate to theories of modality.
As such, there might not be a single theory like multiple realizability which creates a strong objection to be overcome, but rather myriad open questions about semantics itself that prevents reductionists from articulating a strong theory. RTM, consciousness, and the study of semantics is still a bit of a frontier, and mastering its intricacies means focusing not only on historical arguments such as those Descartes makes, but on an increasingly divergent philosophies-of and sciences to find meaning in the discussion. One can say that as computer technologies increasingly become sophisticated potentially drawing from bigger distributed systems, quantum computing, and broader and stronger narrow-AI, it will certainly continue to be a lively debate at what point if ever AI can be said to possess intentionality, meaning, self-awareness, and maybe a theory of mind. This after all, may be the proof in the pudding one day to show that meaning and human-level intelligence reduce to sophisticated systems of physical computation (SEP).