Janus
Page 5
Unfortunately, the term 'hierarchy' itself is rather unattractive and often provokes a strong emotional resistance. It is loaded with military and ecclesiastic associations, or evokes the 'pecking hierarchy' of the barnyard, and thus conveys the impression of a rigid, authoritarian structure, whereas in the present theory a hierarchy consists of autonomous, self-governing holons endowed with varying degrees of flexibility and freedom. Encouraged by the friendly reception of the holon, I shall occasionally use the terms 'holarchic' and 'holarchy', but without undue insistence.
6
We have seen that biological holons, from organisms down to organelles, are self-regulating entities which manifest both the independent properties of wholes and the dependent properties of parts. This is the first of the general characteristics of all types of holarchies to be retained; we may call it the Janus principle. In social hierarchies it is self-evident: every social holon -- individual, family, clan, tribe, nation, etc. -- is a coherent whole relative to its constituent parts, yet at the same time part of a larger social entity. A society without holarchic structuring would be as chaotic as the random motions of gas molecules colliding and rebounding in all directions.*
* However, the situation is somewhat obscured by the fact that complex
societies are structured by several interlocking hierarchies --
see below, section 12.
Not quite as obvious at first glance is the hierarchic organization of our skilled activities. The skill of driving a motor-car does not consist in the conscious activation of individual muscles by the driver's brain, but in the triggering of sub-routines like accelerating, braking, steering, changing gears, etc., each of which represents a quasi-autonomous pattern of activities -- a behavioural holon which is so self-reliant that once you have mastered the skill of driving a particular car, you can drive any car.
Or, take the skill of communicating ideas by speech. The sequence of operations starts at the apex of the hierarchy with the intention of conveying the idea or message. But that idea is as often as not of a pre-verbal nature; it may be a visual image, a feeling, a vague impression. We are familiar with the frustrating experience of knowing what we want to say, but not knowing how to express it; and this refers not only to the search for the right word, but preceding that, to the structuring of the intended message and arranging it in a sequential order; processing it according to the laws of grammar and syntax; and lastly, activating coordinated patterns of muscle contractions in the tongue and vocal chords. Thus speaking involves the stepwise concretization, elaboration and articulation of originally inarticulate mental contents. Although these operations follow each other very fast and to a large extent automatically, so that we are not consciously aware of them, they nevertheless require a succession of different activities on different levels of the mental hierarchy. And each of these levels has its own laws: the laws of enunciation, the rules of grammar and syntax, the canons of semantics, etc.
From the listener's point of view the sequence of operations is reversed. It starts at the lowest level -- the perceptual skills of recognizing phonemes (speech sounds) in the air-vibrations reaching the ear-drums, amalgamating them into morphemes (syllables, prefixes, etc.) and so forth, through words and sentences, finally reconstituting the speaker's message at the apex of the hierarchy.
Let us note that nowhere on the upward or downward journey through the linguistic holarchy do we encounter hard and indivisible 'atoms of language'. Each of the entities on various levels -- phonemes, morphemes, words, sentences -- is a whoJe relative to its parts, and a subordinate part of a more complex entity on the next higher level. For instance, a morpheme like /men/ is a linguistic holon which can be put to many uses -- menace, mental, mention, mentor, etc.; and which particular meaning it will assume depends on the context on the higher level.
Psycholinguists use the branching tree as a convenient model for this step-by-step process of spelling out an implicit thought in explicit terms, of converting the potentialities of an amorphous idea into the actual motion-patterns of the vocal chords. This remarkable process has been compared to ontogenesis -- the development of the embryo; first, there is the fertilized egg, which contains all the potentialities defining the finished product, the 'idea', as it were, of the future individual: these potentials are then 'spelt out' in successive stages of differentiation. It may also be compared to the process by which a military action is carried out: the order 'Eighth Army will advance in the direction of Tobruk', issued from the apex of the hierarchy by the general in command is concretized, articulated and spelt out in more detail at each of the successive lower echelons.
Generally speaking, the performance of any purposeful action, whether instinctive, like the nest-building of birds, or acquired as most human skills are, follows the same pattern of spelling out a general intent by the stepwise activation or triggering of functional holons -- sub-routines -- on successively lower levels of the hierarchy. This rule is universally applicable to all types of 'output hierarchies', regardless whether the 'output' is a human baby, a sentence spoken in English, the playing of a piano sonata or the action of tying one's shoelaces. (For input hierarchies, as we shall see later, the reverse sequence holds.)
7
The next point to emphasize is that every level in a hierarchy of any type is governed by a set of fixed, invariant rules, which account for the coherence, stability, and the specific structure and function of its constituent holons. Thus in the language hierarchy we found on successive levels the rules which govern the activities of the vocal chords, the laws of grammar and above them the whole semantic hierarchy concerned with meaning. The codes which govern the behaviour of social holons, and lend them coherence, are written and unwritten laws, traditions, belief -- systems, fashions. The development of the embryo is governed by the 'genetic code'. Turning to instinctive activities, the web which the spider weaves, the nest which the blue tit builds, and the courting ceremony of the greylag goose all conform to fixed, species-specific patterns, produced according to certain 'rules of the game'. In symbolic operations, the holons are rule-governed cognitive structures variously called 'frames of reference', 'associative contexts', 'universes of discourse', 'algorithms', etc., each with its specific 'grammar' or canon. We thus arrive at a tentative definition: the term 'holon' may be applied to any structural or functional sub-system in a biological, social or cognitive hierarchy, which manifests rule-governed behaviour and/or structural Gestalt-constancy.* Thus organelles and homologous organs are evolutionary holons; morphogenetic fields are ontogenetic holons; the ethologist's 'fixed action-patterns' and the sub-routines of acquired skills are behavioural holons; phonemes, morphemes, words, phrases are linguistic holons; individuals, families, tribes, nations are social holons. **
* The 'or' is necessary to include configurations in symbolic
hierarchies -- which do not manifest 'behaviour' in the usual sense.
** Various authors have pointed to certain affinities between the
concept of the holon and Ralph Gerard's 'org'. Thus D. Wilson
in Hierarchical Structures: 'Koestler (1967) elects to
designate these "Janus-faced" entities by the term holon
. . . We note that Gerard uses the term org to designate the
same concept (Gerard, 1957).' This of course amounts to a veiled
hint at plagiarism. The two quotations from Gerard that follow
indicate the similarities and differences between his org
and the holon (my italics): 'Those material systems
or entities which are individuals at a given level but are composed
of subordinate units, lower level orgs'. [13] The limitation to
'material systems' is made more explicit in the second quotation,
where he defines the org as 'that sub-class of systems
composed of material systems, in which matter enters into the
picture; this excludes formal systems, for example.' [14]
Thus
the term 'org' cannot be applied to behavioural or linguistic
or cognitive hierarchies where the concept of the holon proved
especially useful. Orgs, as defined by Gerard, represent a
sub-category of holons confined to material systems.
8
The set of fixed rules which govern a holon's structure or function we shall call its code or canon. However, let us note at once that while the canon imposes constraints* and controls on the holon's activities, it does not exhaust its degrees of freedom, but leaves room for more or less flexible strategies, guided by the contingencies of the environment. This distinction between fixed (invariant) codes and flexible (variable) strategies may sound at first a little abstract, but it is fundamental to all purposeful behaviour; a few examples will illustrate what is meant.
* 'Constraint' is a rather unhappy scientific term (reminiscent of
the strait-jacket) which refers to the rules which govern organized
activity.
The common spider's web-making activities are controlled by a fixed inherited canon (which prescribes that the radial threads should always bisect the laterals at equal angles, thus forming a regular polygon); but the spider is free to suspend his web from three, four or more points of attachment -- to choose his strategy according to the lie of the land. Other instinctive activities -- birds building nests, bees constructing their hives, silkworms spinning their cocoons -- all have this dual characteristic of conforming to an invariant code or rule -- book which contains the blueprint of the finished product, but using amazingly varied strategies to achieve it.
Passing from the instinctive activities of the humble spider to sophisticated human skills like playing chess, we again find a code of fixed rules which define the permissible moves, but the choice of the actual move is left to the player, whose strategy is guided by the environment -- the distribution of the chessmen on the board. Speech, as we saw, is governed by various canons on various levels, from semantics through grammar down to phonology, but on each of these levels the speaker has a vast variety of strategic choices: from the selection and ordering of the material to be conveyed, through the formulation of paragraphs and sentences, the choice of metaphors and adjectives, right down to enunciation -- the selective emphasis placed on individual vowels. Similar considerations apply to the pianist improvising variations on a theme. The fixed 'rule of the game' in this case is the given melodic pattern, but he has almost infinite scope for the strategic choices in phasing, rhythm, tempo or transposition into a different key.* A lawyer's activities are very different from a pianist's but the lawyer, too, operates within fixed rules laid down by statute and precedent, while he disposes of a vast range of strategies in interpreting and applying the law.
* Incidentally, transposition of a musical theme into a different key
on the piano, where the sequence of finger movements is totally
different, amounts to a complete refutation of the behaviourists'
chain-response theory.
9
In ontogenesis -- the development of the embryo -- the distinction between 'rules' and 'strategies' is at first sight less obvious, and requires a slightly longer explanation.
The apex of the hierarchy in this case is the fertilized egg; the axis of the inverted tree represents time: and the holons on successive lower levels represent successive stages in the differentiation of tissues into organs. The growth of the embryo from a shapeless blob to a 'roughed in' form and through various stages of increasing articulation has been compared to the way in which a sculptor carves a figure out of a block of wood -- or, as already mentioned, to the 'spelling out' of an amorphous idea into articulate phonemes.
The 'idea' to be spelt out in ontogeny is contained in the genetic code, housed in the double helix of nucleic acid strands in the chromosomes. It takes fifty-six generations of cells to produce a human being out of a single, fertilized egg-cell. The cells in the growing embryo are all of identical origin, and carry the same set of chromosomes, i.e., the same hereditary dispositions. In spite of this, they develop into such diverse products as muscle cells, kidney cells, brain cells, toe-nails. How can they do this if they are all governed by the same set of laws, by the same hereditary canon?
This is a question which, as W. H. Thorpe recently wrote, 'we are not yet within sight of being able to answer'. [15] But at least we can approach it by a rough analogy. Let the chromosomes be represented by the keyboard of a grand piano -- a very grand piano with a few thousand million keys. Then each key will represent a gene or hereditary disposition. Every single cell in the body carries a complete keyboard in its nucleus. But each specialized cell is only permitted to sound one chord or play one tune, according to its speciality -- the rest of the keyboard having been sealed off by scotch-tape.*
* This sealing-off process also proceeds step-wise, as the hierarchic
tree branches out into more and more specialized tissues -- see
The Ghost in the Machine, Ch. IX, and below, Part Three.
But this analogy immediately poses a further problem: quis custodiet ipsos custodes -- who or what agency decides which keys the cell should activate at what stage and which should be sealed off? It is at this point that the basic distinction between fixed codes and adaptable strategies comes in once again.
The genetic code, defining the 'rules of the game' of ontogeny, is located in the nucleus of each cell. The nucleus is bounded by a permeable membrane, which separates it from the surrounding cell-body, consisting of a viscous fluid -- the cytoplasm -- and the varied tribes of organelles. The cell-body is enclosed in another permeable membrane, which is surrounded by body-fluids and by other cells, forming a tissue; this, in turn, is in contact with other tissues. In other words, the genetic code in the cell -- nucleus operates within a hierarchy of environments like a nest of Chinese boxes packed into each other.
Different types of cells (brain cells, kidney cells, etc.) differ from each other in the structure and chemistry of their cell-bodies. These differences are due to the complex interactions between the genetic keyboard in the chromosomes, the cell-body itself, and its external environment. The latter contains physico-chemical factors of such extreme complexity that Waddington coined for it the expression 'epigenetic landscape'. In this landscape the evolving cell moves like an explorer in unknown territory. To quote another geneticist, James Bonner, each embryonic cell must be able to 'test' its neighbour-cells 'for strangeness or similarity, and in many other ways'. [16] The information thus gathered is then transferred -- 'fed back' -- via the cell-body to the chromosomes, and determines which chords on the keyboard should be sounded, and which should be temporarily or permanently sealed off; or, to put it differently, which rules of the game should be applied to obtain the best results. Hence the significant title of Waddington's important book on theoretical biology: The Strategy of the Genes. [17]
Thus ultimately the cell's future depends on its position in the growing embryo, which determines the strategy of the cell's genes. This has been dramatically confirmed by experimental embryology: by tampering with the spatial structure of the embryo in its early stages of development, the destiny of a whole population of cells could be changed. If at this early stage the future tail of a newt embryo was grafted into a position where a leg should be, it grew not into a tail, but into a leg -- surely an extreme example of a flexible strategy within the rules laid down by the genetic code. At a later stage of differentiation the tissues which form the rudiments of future adult organs -- the 'organ-buds' or 'morphogenetic fields' -- behave like autonomous self-regulating holons in their own right. If at this stage half of the field's tissue is cut away, the remainder will form, not half an organ, but a complete organ. If the growing eye-cup is split into several parts, each fragment will form a smaller, but normal eye.
There is a significant analogy between the behaviour of embryos at this advanced stage and that very early, blastular stage, when it sti
ll resembles a hollow ball of cells. When half the blastula of a frog is amputated, the remainder will develop not into half a frog but a smaller normal frog; and if a human blastula is split by accident, the result will be twins or even quadruplets. Thus the holons which at that earliest stage behave as parts of the potentially whole organism manifest the same self-regulating characteristics as the holons which at a lower (later) level of the developmental hierarchy are parts of a potential organ; in both cases (and throughout the intermediary stages) the holons obey the rules laid down in their genetic code but retain sufficient freedom to follow one or another developmental pathway, guided by the contingencies of their environment.
These self-regulating properties of holons within the growing embryo ensure that whatever accidental hazards arise during development, the end-product will be according to norm. In view of the millions and millions of cells which divide, differentiate, and move about, it must be assumed that no two embryos, not even identical twins, are formed in exactly the same way. The self-regulating mechanisms which correct deviations from the norm and guarantee, so to speak, the end-result, have been compared to the homeostatic feedback devices in the adult organism -- so biologists speak of 'developmental homeostasis'. The future individual is potentially predetermined in the chromosomes of the fertilized egg; but to translate this blueprint into the finished product, billions of specialized cells have to be fabricated and moulded into an integrated structure. It would be absurd to assume that the genes of that one fertilized egg should contain built-in provisions for each and every particular contingency which every single one of its fifty-six generations of daughter-cells might encounter in the process. However, the problem becomes a little less baffling if we replace the concept of the 'genetic blueprint', which implies a plan to be rigidly copied, by the concept of a genetic canon of rules which are fixed, but leave room for alternative choices, i.e., adaptive strategies guided by feedbacks and pointers from the environment.