Philosophical considerations and brain models

To what extent is it difficult to put these two points together is to be seen on the instance of Karl Popper's philosophical theory as applied in John Eccles' brain research.[5]

In the Karl Popper's ontology the world of meanings and of the logic struc­ture of their interrelations has been considered as an intersubjective, in­ter­in­di­vidual world that is completely detached from the subjective world of our indi­vi­dual conscious experiences. This latter has been conceived by Pop­per as equally detached from the complete material world. The material world (including the human brain and man-made objects) is considered in that ontology as a World 1, paralleled with the World 2 of conscious phe­no­me­na (including in addition to direct environmental and intraorganizational ex­pe­riences memories, thoughts, and even the self, as the subject of all these ex­periences) and the World 3 of meanings interacting with those other worlds.

When investigating about the ontological status of the “World 3”, Karl Pop­per pointed out that it includes together with contents of mea­nings also the forms of their interrelations. This latters are considered by Popper to be pre-eminently “World 3” entities. He conceded that meanings may be em­bo­died in such “World 1” objects that come to exist as ob­jec­tivations of human ac­ti­vi­ty; but as regards logical, mathematical or other interrelations he preclu­des such a possibility, insisting that they exist nowhere but in the “World 3”.

Not even in the “World 2”, contrary to a rather widespread error in psy­cho­logical thought: such relations cannot be reduced to processes of individual con­sciousness or to their products stored in individual memory. It is why the sub­jective consciousness of an individual may investigate upon them, find cont­ra­dictions and look for their solution, i.e., have the same activity with them as with “World 1” objects that are self-evidently detached from that consciously subjective world.

The brain model of John Eccles.

Now, at the Sixteenth World Congress of Philosophy[6], at a specially organized by philosophers, brain researchers, and psychologists symposium on interrelation between brain and experiences, whether conscious or unconscious, Eccles had the opportunity of presenting his brain model correlated with Popper's philosophical model of those three interacting worlds. And Popper's co-author labelled his theory dualist interactionalism: the “World 3” had been completely missing from it. It is worth seeing his arguing in some details: Eccles (and in their jointly written book Popper as well) rejects the theory of epiphenomenalism, according to which there is nothing but a reciprocal influence between the brain and the external world and if in the meantime some phenomena of awareness and self-awareness happen to arise, this would allegedly be nothing but an epiphenomenon that would have no effect whatever on the reciprocating process. On the contrary, Eccles claimes that the self-reliant “World 2” of awareness and self-awareness itself establishes a reciprocating relationship with the “World 1” of the brain (for its part, interacting with the external reality) – hence the designation “dualist interactionalism.” Now, if in the meantime some phenomena of a “World 3” of interraleted to each other meanings happen to arise, this would, Eccles suggests, be nothing but an epiphenomenon that would have no effect whatever on that reciprocating process between “World 2” and “World 1”. Epiphenomenalism survived; it merely moved up one level within the system of interconnections.

From the point of view of this “World 3” epiphenomenalism, it is worth­while to look at the arguments that prompted Eccles to reject a “World 2”-related epiphenomenalism. The argument originated with Pop­per, who, in his chapters of the book they jointly wrote, pointed out that:

“From a Darwinian point of view, we must consider the survival value of mental processes... Darwinists must look at “soul" – i.e., mental processes and our ability to form mental actions and reactions as a bodily organ that developed under the pressure of natural selection... The Darwinist point of view must be this: consciousness and, in general, mental processes must be viewed (and, if possible, explained) as the results of development in the course of natural selection.[7]

“World 2”'s phenomena develop in tandem with the increase in the brain's complexity, Eccles speculated at the World Congress of Philosophy; and yet, according to the theory of evolution only those structures and processes develop in the course of natural selection that contribute significantly to survival. If “World 2” is impotent, then the theory of evolution cannot explain its development.

As a matter of fact, we must consider exactly the same logic as applicable also to the “World 3” of interindividual phenomena.

In his presentation, Eccles (staying within the first two “Worlds”) summarized what was known of the brain's fine-grained mechanisms at the time of the World Congress of Philosophy: what we know of the location of nerve cells, and of their connection with each other. He pointed out that the mechanism revealed by brain research is not adapted for transforming physical stimuli put in from the environment into mental phenomena manifesting themselves at the output of the system (in purposeful behavior, speech). Consequently, we must assume either that conscious phenomena do not exist even at the output of the central nervous system; or that they already exist at its input. And the first assumption is rejected by Eccles on the basis of the above Darwinian considerations.

Therefore, Eccles's final conclusion at the World Congress of Philo­so­phy was that “the self conscious mind” a priori exists as a “World 2”, and that a part of the cortex's operating units (of the 2 million modules, each one respectively constructed of some 5,000 nerve cells[8]) form a “liai­son brain”[9] that serves as a window from the “World 1” to the “World 2”.

The logic of natural sciences.

Theoretical conclusions of Eccles (and of most other brain researchers) are supported by a logic that all natural sciences inherited from classic mechanics. “From earlier theories we have taken over the idea of corpuscles, together with the scientific vocabulary based on it” – pointed out the Nobel-prize winner Schrödinger, adding: “This concept is not correct. It constantly prompts our thinking to seek explanations that obviously make no sense at all. Its thought structure contains elements that do not exist in real corpuscles.” Of all natural sciences, it was physics that first deviated from this logic, when, following its series of crises around the turn of the century, it presented the concept that “everything – absolutely everyting – is corpuscle and field at the same time. All matter has its continuous structure, represented by a field, as well as its discrete structure, represented by a corpuscle.”[10]

Returning to our problem, here the “explanations that obviously ma­ke no sense at all”, search for which is prompted by the corpuscle-orien­ted lo­gic of our thinking, are related to the question: How does the state of a spa­ti­ally delimited individual body influences the states of other bo­dies that are detached from the former – a neuron other nerve cells, a mo­dule of neu­rons other modules, a precise part of the nervous system its other parts, or the integer nervous system other bodily organs? Now, the ans­wer made out by a “corpuscular logic” is that spatially defined bodies on­ly in­ter­act to the extent that they enter into spatial contact along their circumferences.

It was this very logic that has always been applied, in particular, for un­derstanding meaning although for such a logic this latterhas always re­mai­ned enig­matic. Since the controversy between Platon and Antisthenis it has been hard to settle whether meaning is located within the spatially de­li­mi­ted bodies of individual things, or it exists as an idea detached from eve­ry one at them. It is still more hard to say whether, while an indi­vi­dual or­ga­nism gets into contact with an external individual object, meaning will or will not be transferred into the organism from the thing (where, as it has just been pointed out, one was unable to say whether meaning was inherent).

Finally, it is the least possible at all to decide whether meaning has a mental impact only when it finds its way into an individual organism. “Corpuscular logic” tries to cope with meaning by transforming it into familiarity: as if meaning would have been transferred from the thing into the organism and by now fixed in one of its parts that is, in principle, identifiable as responsable for the memory of this organism. On the other hand, one may not a priori discard the possibility that meaning may have a mental impact even when detached from all individual organisms being located in a supraindividual system of language, culture etc. (just the same way as it “in itself” is perhaps detached from all individual things).

If “corpuscular logic” does take into consideration this latter possibility, nevertheless it imposes its own terms upon the facts. First of all, it represents language as a store of particular corpuscules (i. e. a priori given labels), that would carry meanings (also supposed to be given a priori) the way real things would be expected by the “corpuscular logic” to do. Again, such a logic may only conceive the way meaning carried by a linguistic label becomes a psychic factor if that linguistic label, being contacted by an individual, turns from external into internal factor: finds, through some coding process, a corpuscular vehicle located in a theoretically well identifiable locus in the individual body. According such a logic, without getting into an, at least, indirect connection with the individual body the fact that language includes meanings would be psychologically just as irrelevant as is that other fact of things being given in this individual body's environmentbefore setting up their contact.

The brain model of John Szentagothai.

The reason for which Eccles has not dealt with such (and any other) kind of “World 3” problems and the one for which he made the above statement about the brain's structure being not adapted for transforming physical stimuli put in from the environment into mental phenomena manifesting themselves at the output of the brain, relies on the same “corpuscular logic”.

While this logic forced Eccles to search after answers to questions which, according to Schrödinger's reasoning, are incorrectly put, J. Szentagothai reached entirely different theoretical conclusions when starting from the same facts (discovered in part by Eccles' research). Although the model he proposed for the structure and operation of the cerebral cortex acknowledges the cortex to be “a wonderfully precise neurological machine with a genetically defined "set of wires",” he admits that “superimposed on this is an... intermittent and mutually symmetrical (quasi-random) system of connections.”[11] According to the first part of this description, therefore, the cortex has a corpuscle-type structure; the second part, however, reveals a structure similar to one of a field: states are defined in it, but the constellation of corpuscles realizing each of these states gets organized only afterwards, as a “dynamic pattern” of a quasi-random system of connections.

What Szentagothai suggests is this: Even though we cannot consider the brain's precisely wired structure as a mechanism whose operation would yield a mental phenomenon, such a result can indeed be produced by a brain that we view as a dynamic pattern emerging in the course of its operation.

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