Mjesec: Kolovoz 2013
Američki neuroznanstvenik Paul D. MacLean predložio je 1960-ih jedan trostruki model evolucije mozga sisavaca nazvan triune brain.
Model nije općeprihvaćen, ali nije ni odbačen, mada se čini da ima više poklonika među psihijatrima nego među neuroznanstvenicima. Iz zaključka članka Detlev W. Ploog, The place of the Triune Brain in psychiatry, iz 2003.:
MacLean’s sophisticated work culminating in the concept of the triune brain is the single and most useful concept we have for linking evolutionary psychiatry and neuroscience with concepts of the social sciences. …
MacLean was the first in neuroscience who showed concerns for the neural substrate of subjective experience, which is central to psychoanalysis. The limbic system derives subjective information in terms of emotional feelings that guide behavior required for selfpreservation and preservation of the species. To take this one step further, Jung, the Swiss psychiatrist and Freud’s adversary who developed the idea of archetypes, assigned the brainstem to the site of origin of archetypical dreams, that is, dreams of impersonal content dealing with species-specific behaviors and experiences, so-called great dreams. In MacLean’s concept, it is the striatal complex, the protoreptilian brain.
O tom modelu je 1986. pisao Carl Sagan u knjizi The Dragons of Eden: Speculations on the Evolution of Human Intelligence. Meni je, naravno, zanimljiv zbog analogije s Platonovom trostrukom psihom, a koja nije promakla ni Saganu.
One of the most engaging views of the subsequent evolution of the brain is a story of the successive accretion and specialization of three further layers surmounting the spinal cord, hindbrain and midbrain. After each evolutionary step, the older portions of the brain still exist and must still be accommodated. But a new layer with new functions has been added.
The principal contemporary exponent of this view is Paul MacLean, chief of the Laboratory of Brain Evolution and Behavior of the National Institute of Mental Health. One hallmark of MacLean’s work is that it encompasses many different animals, ranging from lizards to squirrel monkeys. Another is that he and his colleagues have studied carefully the social and other behavior of these animals to improve their prospects of discovering what part of the brain controls what sort of behavior. …
From experiments such as those with squirrel monkeys, MacLean has developed a captivating model of brain structure and evolution that he calls the triune brain. “We are obliged,” he says, “to look at ourselves and the world through the eyes of three quite different mentalities,” two of which lack the power of speech. The human brain, MacLean holds, “amounts to three interconnected biological computers,” each with “its own special intelligence, its own subjectivity, its own sense of time and space, its own memory, motor, and other functions.” Each brain corresponds to a separate major evolutionary step. The three brains are said to be distinguished neuroanatomically and functionally, and contain strikingly different distributions of the neurochemicals dopamine and cholinesterase. …
MacLean has distinguished three sorts of drivers of the neural chassis. The most ancient of them surrounds the midbrain… We share it with the other mammals and the reptiles. It probably evolved several hundred million years ago. MacLean calls it the reptilian or R-complex. Surrounding the R-complex is the limbic system, so called because it borders on the underlying brain. (Our arms and legs are called limbs because they are peripheral to the rest of the body.) We share the limbic system with the other mammals but not, in its full elaboration, with the reptiles. It probably evolved more than one hundred and fifty million years ago. Finally, surmounting the rest of the brain, and clearly the most recent evolutionary accretion, is the neocortex. Like the higher mammals and the other primates, humans have a relatively massive neocortex. It becomes progressively more developed in the more advanced mammals. The most elaborately developed neocortex is ours (and the dolphins’ and whales’). It probably evolved several tens of millions of years ago, but its development accelerated greatly a few million years ago when humans emerged. …
[W]e should expect the R-complex in the human brain to be in some sense performing dinosaur functions still; and the limbic cortex to be thinking the thoughts of pumas and ground sloths. Without a doubt, each new step in brain evolution is accompanied by changes in the physiology of the preexisting components of the brain. The evolution of the R-complex must have seen changes in the midbrain, and so on. What is more, we know that the control of many functions is shared in different components of the brain. But at the same time it would be astonishing if the brain components beneath the neocortex were not to a significant extent still performing as they did in our remote ancestors.
MacLean has shown that the R-complex plays an important role in aggressive behavior, territoriality, ritual and the establishment of social hierarchies. Despite occasional welcome exceptions, this seems to me to characterize a great deal of modern human bureaucratic and political behavior. I do not mean that the neocortex is not functioning at all in an American political convention or a meeting of the Supreme Soviet; after all, a great deal of the communication at such rituals is verbal and therefore neocortical. But it is striking how much of our actual behavior-as distinguished from what we say and think about it- can be described in reptilian terms. We speak commonly of a “cold-blooded” killer. Machiavelli’s advice to his Prince was “knowingly to adopt the beast.” …
I want to be very clear about the social implications of the contention that reptilian brains influence human actions. If bureaucratic behavior is controlled at its core by the R-complex, does this mean there is no hope for the human future? In human beings, the neo-cortex represents about 85 percent of the brain, which is surely some index of its importance compared to the brainstem, R-complex and limbic system. Neuro-anatomy, political history, and introspection all offer evidence that human beings are quite capable of resisting the urge to surrender to every impulse of the reptilian brain. There is no way, for example, in which the Bill of Rights of the U.S. Constitution could have been recorded, much less conceived, by the R-complex. It is precisely our plasticity, our long childhood, that prevents a slavish adherence to genetically preprogrammed behavior in human beings more than in any other species. But if the triune brain is an accurate model of how human beings function, it does no good whatever to ignore the reptilian component of human nature, particularly our ritualistic and hierarchical behavior, On the contrary, the model may help us to understand what human beings are about. (I wonder, for example, whether the ritual aspects of many psychotic illnesses-e. g., hebephrenic schizophrenia-could be the result of hyperactivity of some center in the R-complex, or of a failure of some neocortical site whose function is to repress or override the R-complex. I also wonder whether the frequent ritualistic behavior in young children is a consequence of the still-incomplete development of their neocortices.)
In a curiously apt passage, G. K. Chesterton wrote: “You can free things from alien or accidental laws, but not from the laws of their own nature. . . . Do not go about . . . encouraging triangles to break out of the prison of their three sides. If a triangle breaks out of its three sides, its life comes to a lamentable end.” But not all triangles are equilateral. Some substantial adjustment of the relative role of each component of the triune brain is well within our powers. …
The limbic system appears to generate strong or particularly vivid emotions. This immediately suggests an additional perspective on the reptilian mind: it is not characterized by powerful passions and wrenching contradictions but rather by a dutiful and stolid acquiescence to whatever behavior its genes and brains dictate.
Electrical discharges in the limbic system sometimes result in symptoms similar to those of psychoses or those produced by psychedelic or hallucinogenic drugs. In fact, the sites of action of many psychotropic drugs are in the limbic system. Perhaps it controls exhilaration and awe and a variety of subtle emotions that we sometimes think of as uniquely human.
The “master gland,” the pituitary, which influences other glands and dominates the human endocrine system, is an intimate part of the limbic region. The mood-altering qualities of endocrine imbalances give us an important hint about the connection of the limbic system with states of mind. There is a small almond-shaped inclusion in the limbic system called the amygdala which is deeply involved in both aggression and fear. Electrical stimulation of the amygdala in placid domestic animals can rouse them to almost unbelievable states of fear or frenzy. … Malfunctions in the limbic system can produce rage, fear or sentimentality that have no apparent cause. …
There are reasons to think that the beginnings of altruistic behavior are in the limbic system. Indeed, with rare exceptions (chiefly the social insects), mammals and birds are the only organisms to devote substantial attention to the care of their young-an evolutionary development that, through the long period of plasticity which it permits, takes advantage of the large information-processing capability of the mammalian and primate brains. Love seems to be an invention of the mammals. …
Much in animal behavior substantiates the notion that strong emotions evolved chiefly in mammals and to a lesser extent in birds. The attachment of domestic animals to humans is, I think, beyond question. The apparently sorrowful behavior of many mammalian mothers when their young are removed is well-known. One wonders just how far such emotions go. Do horses on occasion have glimmerings of patriotic fervor? Do dogs feel for humans something akin to religious ecstasy? What other strong or subtle emotions are felt by animals that do not communicate with us? …
Chief among the neocortical abstractions are the human symbolic languages, particularly reading and writing and mathematics. … Not all symbolic languages are neocortical however; bees- without a hint of a neocortex-have an elaborate dance language, first elucidated by the Austrian entomologist Karl von Frisch, by which they communicate information on the distance and direction of available food. It is an exaggerated gestural language, imitative of the motions bees in fact perform when finding food-as if we were to make a few steps towards the refrigerator, point and rub our bellies, with our tongues lolling out all the while. But the vocabularies of such languages are extremely limited, perhaps only a few dozen words. The kind of learning that human youngsters experience during their long childhood seems almost exclusively a neocortical function. …
Despite the intriguing localization of function in the triune brain model, it is, I stress again, an oversimplification to insist upon perfect separation of function. … Nevertheless, while bearing these caveats in mind, it seems a useful first approximation to consider the ritualistic and hierarchical aspects of our lives to be influenced strongly by the R-complex and shared with our reptilian forebears; the altruistic, emotional and religious aspects of our lives to be localized to a significant extent in the limbic system and shared with our nonprimate mammalian forebears (and perhaps the birds); and reason to be a function of the neo-cortex, shared to some extent with the higher primates and such cetaceans as dolphins and whales. While ritual, emotion and reasoning are all significant aspects of human nature, the most nearly unique human characteristic is the ability to associate abstractly and to reason. Curiosity and the urge to solve problems are the emotional hallmarks of our species; and the most characteristically human activities are mathematics, science, technology, music and the arts-a somewhat broader range of subjects than is usually included under the “humanities.” Indeed, in its common usage this very word seems to reflect a peculiar narrowness of vision about what is human. Mathematics is as much a “humanity” as poetry. Whales and elephants may be as “humane” as humans. (str. 34.-54.)
Osim opisa samoga modela i odgovarajućeg ljudskog ponašanja, zanimljive su i paralele koje Sagan povlači s Freudovim i Platonovim trostrukim koncepcijama psihe.
The triune-brain model derives from studies of comparative neuroanatomy and behavior. But honest introspection is not unknown in the human species, and if the triune-brain model is correct, we would expect some hint of it in the history of human self-knowledge. The most widely known hypothesis that is at least reminiscent of the triune brain is Sigmund Freud’s division of the human psyche into id, ego and superego. The aggressive and sexual aspects of the R-complex correspond satisfyingly to the Freudian description of the id (Latin for “it”-i. e., the beast-like aspect of our natures); but, so far as I know, Freud did not in his description of the id lay great stress on the ritual or social-hierarchy aspects of the R-complex. He did describe emotions as an ego function-in particular the “oceanic experience,” which is the Freudian equivalent of the religious epiphany. However, the superego is not depicted primarily as the site of abstract reasoning but rather as the internalizer of societal and parental strictures, which in the triune brain we might suspect to be more a function of the R-complex. Thus I would have to describe the psychoanalytic tripartite mind as only weakly in accord with the triune-brain model. …
A superior agreement is found in the metaphor for the human psyche in the Platonic dialogue Phaedrus. Socrates likens the human soul to a chariot drawn by two horses-one black, one white-pulling in different directions and weakly controlled by a charioteer. The metaphor of the chariot itself is remarkably similar to MacLean’s neural chassis; the two horses, to the R-complex and the limbic cortex; and the charioteer barely in control of the careening chariot and horses, to the neocortex.
In yet another metaphor, Freud described the ego as the rider of an unruly horse. Both the Freudian and the Platonic metaphors emphasize the considerable independence of and tension among the constituent parts of the psyche, a point that characterizes the human condition…
Because of the neuroanatomical connections between the three components, the triune brain must itself, like the Phaedrus chariot, be a metaphor; but it may prove to be a metaphor of great utility and depth. (str. 54.-56.)
Prije nešto više od tri godine jedno je otkriće vezano uz Platonove dijaloge dospjelo u masovne medije, npr. u Guardian i Večernji list (novinar VL je nažalost bio pobrkao tekst priopćenja sveučilišta i neke općenite ”izreke” koje kruže po internetu kao Platonove, a bile su navedene ispod priopćenja). Radi se o otkriću Jaya Kennedyja sa sveučilišta u Manchesteru da je Platon brojao riječi svojih dijaloga (to se naziva ”stihometrija”), i pritom primjenjivao jedan matematički obrazac vezan uz pitagorejsko shvaćanje muzika, a koji je su-određivao sadržaj pojedinih dijelova dijaloga.
Otkriće je objavljeno 2010. u časopisu Apeiron, u ovome članku: Plato’s Forms, Pythagorean Mathematics, and Stichometry.
Pročitah ga ponovo, evo nekoliko zanimljvih izvadaka:
The practice of counting the number of syllables in a line or the number of lines in a stanza was already routine in archaic poetry. Vitruvius, without giving his source, reports a tradition that ‘Pythagoreans’ and some comic playwrights mathematically organised longer works. … [T]he practice was already common during Plato’s lifetime. Callimachus’ catalogue, compiled about a century after Plato’s death, recorded the stichometric totals for each of the scrolls in the library of Alexandria. Diogenes Laertius’ report that Aristotle’s writings amounted to 445,270 lines may have derived from the Alexandrian catalogues.In this context, any authors with Pythagorean inclinations could avail themselves of stichometric counts to organise their works. …
This is apparently the first report of computer-based, stichometric investigations of Plato’s dialogues. … Although the data described below reveals some unexpected features of the dialogues, it is in retrospect natural that Plato would have given his works mathematical form. The dialogues reflect the revolution in mathematics that affected several of the arts and sciences during the fifth century, and mathematics is thought to have been important in the early Academy. Plato’s dialogues, of course, generally champion the importance of mathematics for philosophy and education. Embedding mathematical forms in their surface narratives also accords with the dialogue’s core philosophical conception of ‘forms beneath appearances.’ …
Some dialogues, like the Menexenus, the Symposium, and the Phaedrus, contain set speeches clearly demarcated from the surrounding text. The lengths of some of these speeches provide evidence that the composition of each dialogue was stichometrically organised.
In the Menexenus, for example, Socrates’ long speech lasts ten-twelfths of the length of the entire dialogue to within a fraction of a percent.
In the Symposium, Pausanias’ speech, Eryximachus’ speech (including the repartee over Aristophanes’ hiccups), and Aristophanes’ speech are each about one-twelfth of the dialogue. Socrates’ long speech, including his conversations with Agathon and Diotima, occupies three-twelfths or one quarter of the entire dialogue. Alcibiades’ speech lasts about two-twelfths of the dialogue.
These length measurements suggest that an interval of one-twelfth of the dialogue plays a fundamental role. The relative location of the speeches within the Symposium provides an other form of evidence for the importance of this unit. The beginning of Pausanias’ speech is aligned with the point two-twelfths of the way through the dialogue, the beginning of Eryximachus’ speech (with hiccups) with the three-twelfths point, and the beginning of Aristophanes’ speech with the four-twelfths point. The climactic, rhetorical fireworks in praise of Eros that conclude Agathon’s speech occur at sixtwelfths, the centre of the dialogue. This scale of one to twelve plays a role even within the longer speeches. For example, the highlights of Diotima’s speech, her talk of intimate contact with Beauty and her description, at the top of her ‘ladder’, of transcendent Beauty as the form of the One, are aligned with points eight- and nine-twelfths of the way through the dialogue, and thus are also separated by an interval of one-twelfth.
In the Phaedrus, Socrates’ second speech is three times as long as his first speech to within a fraction of a percent. The first speech is somewhat longer than one-twelfth of the dialogue and the second is somewhat longer than three-twelfths. The beginning of the second speech occurs shortly before the four-twelfth point and the end is aligned with the seven-twelfth point.
The structure of arguments within individual dialogues is often organised around this scale of twelfths. Many examples could be given. In the Phaedo, Socrates concludes his argument for immortality from cyclic generation at the third twelfth; immediately thereafter he begins the argument from recollection which concludes at four-twelfths. In the Euthyphro, the first definition of holiness is at three-twelfths and the second definition is at four twelfths. In the Apology, Socrates begins his investigation of the oracle’s claim that he is ‘wisest’ at the two-twelfths point and concludes it at three twelfths. …
Using a figure of thirty-five letters per hexameter line, calculations of the total number of lines in the dialogues produce, with about one or two percent accuracy, impressively round numbers involving multiples of the number twelve:
• The Apology is 1200 lines, or 100 per twelfth.
• The Protagoras, Cratylus, Philebus, and the Symposium are each 2400 lines, or 200 per twelfth.
• The Gorgias is 3600 lines, or 300 per twelfth.
• The Republic is 12,000 lines, or 1000 per twelfth.
• the Laws is 14,400 lines, or 1200 lines per twelfth.
In sum, the lengths of speeches, the position of speeches within the dialogues, the location of significant turns in the arguments, and the absolute lengths of the dialogues all provide evidence for an underlying stichometric organisation and, in particular, for the importance of a twelve-part structure.
This evidence for a common twelve-part stichometric structure within individual dialogues suggests that they be read side-by-side, in order to compare their structures. Despite the different subjects of the dialogues, such com parisons reveal a surprising number of parallel passages, i.e., passages with similar content at the same relative locations in different dialogues. Many examples could be given. Here one, clear example is considered in a range of dialogues, both early and late. …
The Republic’s discussion of philosopher-kings and the form of the ideal just man occurs at the centre of the dialogue. Comparisons between the dialogues shows that passages describing the divine wisdom and justice of the ideal philosopher often recur near the centre. These terms also, of course, occur elsewhere in the dialogues, and that raises the chance that the following parallels are a coincidence. The immediate argument here against this possibility is simply the specificity, similarity, and precise locations of the passages:
Republic (50.0-50.5p): Socrates seeks justice and the just man who ‘participates’ in it, invokes Zeus, and first mentions the philosopher-kings who will lead (hegemoneuo) the city.
Phaedrus (49.5-50.3p): the followers of Zeus, the god of justice, seek a beloved with a ‘philosophical’ nature, who is a leader (hegemonikos), and ‘participates’ in the nature of god. The followers of Hera, on the other hand, seek a beloved with a ‘kingly’ nature.
Symposium (49.4-50.0p): Agathon praises Eros for being ‘the best and most beautiful leader’ (hegemon) and for being a ‘spectacle to the wise and admirable to the gods’ (including Zeus), and Socrates, perhaps for Plato an ideal philosopher and embodiment of Eros, jocularly claims to be a prophet (generally, a kind of divine knowledge).
Apart from the explicit repetition of forms of ‘hegemon,’ these three passages share a number of elements: Zeus and justice, the philosopher’s relation to divinity, and the notion of ruling or leading.
The Cratylus is useful for investigating parallels between the dialogues. Its series of etymologies is not organised in detail by any over-arching argument or narrative; the locations of the various terms analysed there, which typically appear only once, is generally determined by the underlying network of parallels between the dialogues. Here, for example, our leitmotiv occurs at the centre and nowhere else:
Cratylus (47.7-51.3p): the etymologies of wisdom, knowledge, the good, justice, Zeus, and of nous which rules itself and orders all things.
Some dialogues show this ideal philosopher in action at their centre, and repeat the cluster ‘philosophy, justice, and god’:
Apology (49.1-50.7p): Socrates claims to be wiser because he knows nothing — except that injustice is wrong for man and god, he will not give up philosophy, and he will obey the god.
Euthydemus (48.6-49.9p): one must philosophise, knowledge is more valuable than gold, and knowledge makes one immortal.
Euthyphro (48-50p): the gods dispute about justice, Socrates seeks to become wiser by being taught what the gods believe is correct (i.e., just), and will sing the praises of wisdom.
Gorgias (49.1-50.1p): Socrates asks about the nature of wisdom, behaves like an ideal philosopher by admitting his ignorance and seeking correction, and doubts whether justice is the stronger ruling over the weaker.
Finally, the Timaeus interrupts a long passage on natural philosophy at the centre of the dialogue with a paragraph of Pythagorean theology. Since justice is sometimes for Plato a kind of harmony, this passage would itself constitute an example of just and divine rule:
Timaeus (49.4-49.5p): Necessity willingly or unwillingly obeys God, who harmonises everything in the universe according to precise proportions.
Careful study of the parallels between the dialogues leads to another feature of their shared stichometric structure. Side-by-side comparisons of passages at the same relative locations shows that concepts with negative valuations within the dialogues, like disease, dishonesty, Hades, the body, difference, and negation, tend to cluster in definite ranges and at a definite locations, such as around and between the points ten and eleven twelfths of the way through the dialogues. Similarly, positive concepts, like the forms, virtue, the gods, goodness, justice, and the soul, tend to occur in distinct and equally definite ranges. These tendencies are never absolute, but the mixture of concepts in these ranges is clearly dominated either by more negative or by more positive concepts…
Za ovo Kennedy daje niz primjera u članku, ali možda slika govori najjasnije (prva se odnosi na Simpozij, druga na Fedon):
Ima još zanimljivih stvari u članku, a i na Kennedyjevom blogu, o čemu u budućim zapisima. Za kraj, zaključak članka:
There are now several kinds of evidence that Plato’s dialogues have a stichometric structure: the lengths of speeches, the alignment of some speeches and key concepts with the twelfths, the parallel passages, and the parallel negative and positive ranges. The musical interpretation of these features is natural and coherent: a twelve-note scale with harmonic and dissonant ranges underlies the surface narrative of the dialogues. The evidence and its interpretation fit the historical context: stichometry was a common practice and applied to Plato’s dialogues, allegory was widely debated, the new mathematics was promoted by Plato and the Academy, the numeric representation of musical scales and harmonic theory were well-known, Plato’s correspondents, colleagues, and followers associated him with Pythagoreanism, and the Neo-Pythagoreans made the scale of twelve, regularly spaced notes part of their studies of the metaphysics allegedly hidden in the dialogues. … Though the evidence reported here will need to be verified and debated, it does clarify, in a surprising way, Aristotle’s once puzzling view that Plato was a Pythagorean.
Kupih novo izdanje (Profil, 2013.) knjige Zvonimira Šikića i Zorana Šćekića Matematika i muzika. Malo sam guglao povodom toga pa pronađoh da Šikić ima blog (!), i na njemu prvo poglavlje te knjige (u dva zapisa):
Treba reći da to početno poglavlje nije reprezentativno za sadržaj knjige, koji je puno više stručan nego u tom poglavlju. Ja sam naučio podosta iz nje, a nisam još sve pročitao (ali nisam znao ništa o muzici, tako da…) Glavni problem je kako se ono što našem sluhu zvuči skladno odnosi spram matematičkih omjera mjerljivih veličina (duljina žica instrumenata i sl., odnosno frekvencija). O tome u ulomku na novom izdanju bloga:
Evo i muzike Zorana Šćekića:
Inače, zabavno mi je da engleski nazivi za dvije vrste ugađanja (just intonation i equal temperament) čuvaju Platonovo razlikovanje između pravednog i jednakog. 🙂
premješteno na novo izdanje bloga: aisthesis-empeiria-tehne-episteme-…-sofia? (ulomak iz Martin Heidegger, Platon: Sophistes)
Na forumčiću za izvaninstitucionalno filosofiranje i srodne djelatnosti nazvanom pjaceta zajednički čitamo zbirku Hans-Georga Gadamera Ogledi o filozofiji umjetnosti, izdanje Zagreb 2003. Link je dolje, smatrajte se pozvanim. 🙂
Doista se malo tko od suvremenih filozofa tako strasno i tako uporno uvijek iznova upuštao u iskustvo, promišljanje i tumačenje umjetnosti kao što je to činio Gadamer. To iskustvo nije bilo toliko vođeno općenitim teoretskim stavovima o tomu što je sama umjetnost, ili štoviše njena bit i smisao, već je izrastalo ponajprije i ponajviše iz neposrednog, kako motrećeg i doživljavajućeg tako i misaonog susreta sa samim pojedinačnim umjetničkim djelima.
Ovom se knjigom htjelo dati pregled Gadamerova razumijevanja različitih vrsta i vidova umjetnosti, a uz to i naznačiti neke od bitnih postaja na dugom putu njegovih promišljanja umjetnosti od 1954. do 1995. godine. (Damir Barbarić, iz Pogovora)
Općenito, nisam se mogao zatvoriti za činjenicu da se iskustvo umjetnosti nekako tiče filozofije. Da je umjetnost pravi organon filozofije, ako ne čak i njezin nadmoćni suputnik, to je bila istina koja je filozofiji njemačke romantike sve do konca idealističkog razdoblja bila postavila njenu obuhvatnu zadaću. Univerzitetska filozofija poslijehegelovske epohe morala je svoje nepriznavanje te istine platiti svojim vlastitim opustošenjem. … Naše povijesno naslijeđe poziva nas da tu istinu ponovno zadobijemo. (Hans-Georg Gadamer, iz Pogovora)