the
scientific
landscape
 modeling 
representation
(models, semantics)
 semiotics 
logic &
reasoning
complexity & metrics sets & numbers
categories
relations
objects
wholes, systems, levels
meaning
meta
linguistic
glossary
formalization
& symbol
manipulation
components & datatypes relations
truth & reality algebras
Location: http://www.cs.mun.ca/~ulf/gloss/wholes.html. By Ulf Schünemann since 2002. Please mail any comments.

Wholes & System Composition Levels

navigation bar: Wholes and Parthood
wholes & system composition levels part-whole relations
different kinds of parthood and compositeness
aggregates (concrete)
=/= sets (conceptual)
ontological status of wholes vs. parts
holism, atomism (allied with reductionism), systemism
 

  1. Whole More Than Sum of Parts?
  2. More Than Sum 1: Interdependency: Aggregates << Systems (Integration << Coordination << Control) also: configurational whole, dependence system
  3. More Than Sum 2: Emergent Properties
  4. Scientific/Ontologic Levels (Strata) - Where New System Properties Emerge
  5. More Than Sum 3: Attribute Invariance under Structural Transformation
[Gestalt] Nicholas Rescher, Paul Oppenheim: Logical Analysis of Gestalt Concepts; Brit. J. for the Philosophy of Science VI(22); Aug 1955.
[WSOU] Ernest Nagel: Wholes, Sums, and Organic Unities; 135-155 in: Daniel Lerner (ed): Parts and Wholes - The Hayden Colloquium on Scientific Method and Concept; The Free Press of Glencoe 1963. reprint from Philosophical Studies III 2; Feb 1952.

Whole More Than Sum of Parts?

«In connection with the subject of reduction and emergence, it is helpful to discuss a familiar notion that is frequently associated with these themes. According to this notion there occurs in nature an important type of individual wholes (which may be physical, biological, psychological, or social) that are not simply "aggregates" of independent members, but are "organic unities"; and such wholes are often characterized by the familiar dicutum that they possess an organization which makes each of them "more than the sum of its parts." ... The first point to note, however, is that words like "whole" and "sum" as commonly employed are unusually vague, ambiguous, and even metaphorical; and until their senses are clarified, it is frequently impossible to assess the worth of statements containing them.» [WSOU 135]

«[I]t is possible to define in a precise manner the words "whole," "part," and "sum" so that "The whole is unequal to the sum of its parts" is not only not logically absurd, but it is in fact logically true. There is, therefore, no a priori reason for dismissing such statements as inevitable nonsense, and the real issue is to determine, when such an assertion is made, in what sense if any the crucial words in it are being used in the given contexts» [WSOU 139]. ... «[W]hen a given system has a special type of organization or structure, a useful definition of "addition," if such can be given, must take into account that mode of organization ... Finally ... though a system has a distinctive structure, it is not in principle impossible to specify that structure in terms of relations between its elementary constituents, and moreover in such a manner that the structure can be correctly characterized as a "sum" whose "parts" are themselves specified in terms of those elements and relations» [WSOU 140].
«[S]ome writer apparently understand by "sum" [in the context of melodies] the unordered class of individual tones ... Accordingly, if the word "sum" is used in this sense in contexts in which the word "whole" refers to a pattern or configuration formed by elements standing to each other in certain relations, it is perfectly true, though trivial, to say that the whole is more than the sum of its parts. As has been noted, however, this fact does not preclude the possibility of analyzing such wholes into a set of elements related to one another in definite ways; nor does it exclude the possibility of assigning a different sense to "sum" so that a melody might then be construed as a sum of appropriately selected prats. It is evident that at least a partial analysis of a melody is effected when it is represented in the customary musical notation» [WSOU 143]

«Consider Köhler's example of what one might regard as the very antithesis of a `true' whole: three stones, selected at random, lying in different continents. Although each of the stones is, to be sure, part of the group of three, this group is not, on the usual understanding of the term, a whole. [footnote: The term aggregate has been employed to characterize such failure to qualify under the intuitive notion of a `true' whole. Actually, the term `aggreagte' has as many senses as there are criteria composing the intuitive notion of a whole: for failure to meet certain of these criteria yields a corresponding type of aggregate.]
Let us summarise the intuitive requirements or conditions of adequacy which underlie talk of wholes. To begin with, the things we are considering as wholes, must, of course, consist (in some sense) of parts. In addition, it would seem that the following conditions must be met:

  1. The whole must possess some attribute in virtue of its status as a whole--an attribute peculiar to it, and characteristic of it as a whole.
  2. The parts of the whole must stand in some special and characteristic relation of dependence with one another; they must satisfy some special condition in virtue of their status as parts of a whole.
  3. The whole must possess some kind of structure, in virtue of which certain specifically structural characteristics pertain to it» [Gestalt 90].
In object-oriented modeling, Henderson-Sellers makes similar demands on the use of any kind of aggregation relationship:
«The whole ... exists because of its parts: without the parts the whole has no meaning. The whole provides at least one emergent capability not found in the parts, and is therefore more than the sum of its parts» [OML/RR, underlining added].
«[F]or the aggregation relationship to be valid, an aggregate (aka., composite) must have at least one emergent propery (a property of the aggregate that cannot be deduced from the evaluation of the properties of the individual components) [Kilov&Ross: IM; 1994]. In addition, at least one property of the composite/aggregate should be dependent upon the value of one or more properties of its components/parts. Furthermore, aggregations are generally considered to be antisymmetric and transitive [Rum+: OOMD]. Also some operations to the aggregate are propagated to the parts [K&R: IM]. An important use of aggregation is in support of abstraction, leading to layered diagrams at different granularities [JMEdwards, BHenderson-Sellers: A coherent notation for OO software engineering; TOOLS 5; Prentice-Hall 1991].» [OPEN/CC, underlining added]

  1. Emergent properties and resultant properties were introduced to OOM by Kilov & Ross's "Information Modeling: An Object-Oriented Approach". Picked up in the following by:
  2. Henderson-Sellers [OPEN/CC]: "OPEN Relationships: Composition and Containment"; JOOP 10(7).
  3. Saksena etal. propose as primary structural properties of object composition: emergent properties + resultant properties + composition relation is a strict order.
    "A Characterization of Aggregation"; International Journal of Computer Systems Science and Engineering.
    "Extending Aggregation Constructs in UML"; UML'98 - First International Workshop.
  4. Henderson-Sellers & Barbier's "What is this thing called aggregation?"; TOOLS 29.
    Henderson-Sellers & Barbier's "Black and White Diamonds"; UML'99.

More Than Sum 1: Interdependency: Aggregates << Systems (Integration << Coordination << Control)

Aggregate << System. «Whether or not two things form a system, they can be assumed to associate (or add physically) to form a third thing. Thus thing a and b, no matter how distant and indifferent, my be assumed to form thing c = a °+ b. In other words, the set of things is closed under the operation °+ of association, physical addition, or juxtapos » [MB4 14].

Consider a gravitional system like the solar system: «However what makes such a system into more than just a naturally integrated whole is the relation of complex interdependence among the determinables [of different parts!]. ...
We may thus schematically define a dependence system, following Rescher and Oppenheim [-> see below], as a collection of objects which form a family under a relation to which a class of determinables apply, such that each member of the family has some determinable from the class which is functionally dependent upon some or all of the determinables of some or all of the remaining members. Grelling and Oppenheim, who were the first to offer a definition of such systems, first called them `determinational systems' (Wirkungssystem), later preferring Koffka's term `functional whole'.» [Parts 345]
«The concept of state space can be used to clarify that of system. The state space of an aggregate or conglomerate of non-interacting things is uniquely determined by the partial state spaces. Morever, since the contributions of the latter are all on the same footing, we may take the total state space to equal the union of the partial state spaces. ... Not so in the case of a system: here the state of every component is determined, at least partly, by the states other system components are in, so that the total state space is no longer the union of the partial state spaces. ... In sum, a thing is an aggregate if and only if its state space equals the union of the state spaces of its components - otherwise it is a (concrete) system» [MB4 22].

«An aggregate or assemblage is a collection of items not held together by bonds, and therefore lacks integrity or unity. Aggregates can be either conceptual or concrete (material). A conceptual aggregate is a set. A concrete or material aggregate, on the other hand, is a compound thing, the components of which are not coupled, linked, connected, or bonded, such as a field constituted by two superposed fields, a celestrial constellation, and a random sample of a biological population.
Because the components of an aggregate do not interact - or do not interact appreciably - the behaviour of each is independent of the behaviour of the others. Consequently, the history of the aggregate is the union of the histories of its members. On the other hand the components of a concrete system are linked [ie. interact], whence the history of the whole differs from the union of the histories of its parts. We shall take the last statement to [be?] an accurate version of the fuzzy slogan of holistic metaphysics, namely The whole is greater than the sum of its parts. ...
A system, then, is a complex object, the component of which are interrelated rather than loose. If the components are conceptual, so is the system; if they are concrete or material, then they constitute a concrete or material system. A theory is a conceptual system, a school is a concrete system of the social kind. ...
[Whether conceptual or concrete,] a system may be said to have a definite composition, a definite environment, and a definite structure. The composition of a system is the set of its components; the environment, the set of items with this it is connected; and the structure, the relations among its components as well as among these and the enviroment. For example, a theory is composed of propositions or statements; its environment is the body of knowledge to which it belongs (e.g. algebra or ecology); and its [internal] structure is the entailment of logical consequence relation. The merger of these three items is a propositional system, ie. a system T composed of a set P of propositions, embedded in a certain conceptual body B, and glued together by the relation |-- of entaiment: in short, T = (P,B,|--). And the composition of a school is the union of its staff and pupils; the environment is the natural and social mileu, and the structure consists of the relations of teaching and learning, managed and being managed, and others. The environment must be included in the description of a system because the behavior of the latter depends critically on the nature of its milieu. But of course in the case of the universe the environment is empty, and so it is in the case of the important fiction known as the free particle (or field)» [
MB4 3f, underlining added].

Degrees of systemicity/integration: [MB4 35, underlining added] «Whatever is a system is also a whole but not conversely: an aggregation of independent components is a whole but not an integrated or unitary one. (Compare a living being with its ashes.) Now systemicity or integration comes in degrees: some systems are more tightly knit than others. The degree of integration depends on the connections or links among a system's components relative to the disintegrating actions of the environment. If the inner couplings are "positive" (or "attractive") and strong, the degree of integration is high; if the links are still positive but weak, the degree of integration is low; and it the links are "negative" (or "repulsive"), there is no systemicity or integration at all. Finally, if some of the links are "positive" while others are "negative", the degree of integration depends on which of them are overriding. For example, a stable atomic nucleus is held together by nuclear forces that overcome the electrical repulsions; and a stable humand community is held together by participation in enterprises of common interest, the value of which is greater than that of rivalry or competition - until of course the latter gets the upper hand.
In the case of physical, chemical, and perhaps also biological systems, what measures their degree of integration is their binding energy or, what comes to the same, their dissociation energy. This is the minimal energy required to dissociate the system into its components. It is zero for an aggregate. But such a measure is not universal: it fails to apply to systems where information links play at least as important an integrating role as forces proper - as is the case with social systems. In short, there is no universal measure of the degree of integration or cohesion of a system.»

System: Integration (structural) << Coordination (functional) [MB4 38] «Finally, another concept relevant to that of systemicity is the notion of coordination, which must be distinguished from that of integration. If integration fails the system undergoes structural breakdown. On the other hand coordination concerns the relation among either components or functions resulting in functional maintainance. If coordination fails the system undergoes functional breakdown. There can be integration without coordation but not conversely. ... »
Coordination << Control [MB4 39] «Coordintation does not exclude inhibition. Quite on the contrary: when coordination is a result of control it includes feedback, which, when negative, is a kind of inhibition. .... But of course there can be coordination without the intervention of a control system. For example the corpus callosum bridges the two brain hemispheres in vertebrates and thus renders their coordination possible but is not a control system iteelf.»

Configurational Whole (= whole with some coordination?). «In an illustrative device of A Meyer, magnetic needles of equal strength are inserted in pieces of cork, and floated, with all like poles upwards, in a basin of water. A strong magnet of unlike pole is placed in a fixed position overhead. The floating magnets arrange or rearrange themselves in a symmetric pattern of one or more concentric circles ... In this type of configuration there exist various dependendecies; for example, the distance of one cork from the nearest adjacent cork depends upon the magnetic strength and the number of other magnets» [Gestalt 95].
«In the general characterisation of the concept of depdendence here exemplified we will have to refer to a set of object which, by virtue of standing in certain specified relations, are said to form a configurational whole, or briefly, a configuration. ... [T]hose relations jointly may always be viewed as constituting one more complex relation, R. An ordered set of objects, p1, p2, ... pn, which stand in the relation R to each other, i.e. for which R(p1, p2, ... pn) holds, will be said to form a configuration of kind R. ... Dependence ... will consist in a (more or less complex) relationship phi--in many cases a functional relationship--between the value of the depdendet attribute for p1, and the values of certain attributes for the parts of the configuration» [Gestalt 95].

«A quantitative attribute f of the part p1 in a configuration of kind R consisting of the n objects p1, p2, ... pn is phi-depdendent upon the class G of quantitative attributes of these objects pi, if phi is a relationship such that in every configuration of kind R the f-value of the first member of this configuration is related by phi to the values which the quantitative attributes in G assume for the parts p1, p2, ... pn.
Thus to assert a dependence relation of this type is to assert a lawlike connection» [Gestalt 95f].
«Electrostatics is the source of the classical example of this concept, employed by Köhler. The charge-density at any point of a given charged, well-insulated electric conductor is phi-dependent upon the charge-densities at the remaining points, relative to a complex condition specifiable in electrostatics. Biological homeostasis also provides an illustration. For example, ... the content of individual ions in one volume of the fuild of an animal is very nearly the same as the ion-content of other, equal volumes» [Gestalt 97].

Dependence system (= each part a bit coordinated). «A configuration is a phi-dependence system relative to a set G of attributes if each part of the configuration has some G-attribute which is phi-dependent upon (some or all of) the G-attributes of (some or all of) the remaining parts» [Gestalt 98].
«The concept of dependence system furnishes a logical reconstruction of the informal conception of an `organic' or `functional' or `integrated' whole. For this is based upon the intuitive requirement that the parts of a whole must stand in some special and characteristic relation of interdependence with one another, in virtue of their status as parts of the whole.
«What we have termed a `dependence system' provides a precisely defined counterpart of what has been described as systems `the behavior of which is not determined by that of their individual elements, but where the part-processes are themselves determined by the intrinsic nature of the whole'. Any dependence system furnishes an example of a whole whose parts have features which are such that knowledge of them cannot, relative to the available theoretical information, be acquired by studying their parts in isolation, but requires information regarding other parts. In consequence, the concept of a dependence system also provides a natural housing for the organismic biologists' claim that `analysis of living processes into the behaviors of distinguishable parts of organisms entails a radical distortion of our understanding of such processes'. The study of the logic of such dependence systems would, thus, be an integral part of a General System Theory in the sense of von Bertalanffy» (1951) [Gestalt 99].


More Than Sum 2: Emergent Properties

Definition: (Un)Derivable Attribute
Let Q be an attribute, in the most general sense, of whole w.
The definition is relative to some decomposition D of w into objects p
which are its Pt-parts, i.e., which are in a (part) relation Pt with w.
Q is a derivable/underivable attribute of w
relative to a set G of attributes and some "theory" T (and relative to D)
if `Q(w)' is/is-not deducible by means of T from the G-characterisation of the D-parts of w.

«(We construe `A is deducible from B my means of C' to exclude the cases
in which A is deducible from B alone or from C alone.)» [Gestalt 93/94].
By `G-characterisation «is meant a sentence which, for any n-adic relation g of G, and any n elements
d1, ... dn of D states whether or not the relation holds between these n elements» [Gestalt 92].
T can also include, eg., «specific descriptive statements about the whole and its parts.
The purely theoretial part of T will consist, in the scientifically interesting cases, of some portion
of established science, i.e. a system of laws which at a given time are well established.»

An attribute is logically (un)derivable if it is (un)derivable relative to an empty theory T.

- Logically vs. scientifically derivable attributes of the whole. For example: shape logically derivable, not the weight. «[T]he weight (Q) of a pile (w) of stones (D) is a D-G-[logically]-underivable attribute of a pile relative to the weights (G) of the constituent stones. This is because the weight of the pile is not a logical consequence of the weights of the constituent stones, since its calculation from these requires a physical law (viz. that weigth is additive).» «[T]he shape of a pile of stones is a D-G-[logically]-derivable attribute of the pile relative to a characterisation of the stones in the pile with respect to certain geometric attributes (including metric relations of position and distance). On the other hand, the shape (i.e. physical, not phenomenological) of the pile will be a D-G-[logically]-underivable attribute if G is confined to attributes of the individual stones, exclusive of their mutual spatial relationships» [
Gestalt 92].
- Derivability relative to the state of science. «An example from chemistry: Let w be a molecule whose parts (D) are four different atoms (or radicals) attached to one carbon atom (called `asymmetric' in this case); let G be the chemical and physical properties of these parts, and T be the laws of stereochemistry. Then a molecule will have the derivable property of being optically opaque, i.e. rotating the plan of vibration of polarised light, since this follows by T from the asymmetry of the carbon atom» [Gestalt 94].
«For example, let w be an atom of any element, D its subatomic particles, G their represently known properties, and T presentday nuclear physics. On this basis, w's possession of a cohesive nucleus is an underivable attribute. As appears from this example, the underivable attributes are of especial scientific interest because they provide open problems for research» [Gestalt 93].
Don't confuse derived with shared vs. unshared
- Q is an unshared attribute [TYPE] of w (relative to D) if Q is possessed by no D part:
«If a pile (w) of round stones (D) has the attribute (Q) of being conical,
this shape is an instance of a D-unshared attribute.»

An unshared attribute is essentially the same as Broad's `collective property'.
- Q is a shared attribute [TYPE] of w (relative to D) if Q is possessed by all of the D parts:
«The attribute of having weight (Q) posses by a pile (w) of stones (D)
is a D-shared attribute of the pile.»

Being a homeomerous whole [parts are of same type as whole] implies having shared attributes (?)

Underivable = Emergent = Holistic = Gestaltqualität. «D-G-T-underivable attributes are closely linked ... to what is usually discussed under the heading of emergence and therefore the case in which the theoretical part of T is a micro-structure theory is especially relevant. ... Indeed, our definition ... is adapted from the definition of `emergence' given by Hempel and Oppenheim» (1948) [Gestalt 93].
«[O]ur discussion has connections with the holistic position in the philosophy of biology ... Our concept of an underived attribute of a whole could, in this connection, be taken as a precise explication of the informal concept of a holistic property
«Special interest attaches to the concept of attributes of a whole underivable from information regarding its parts even by using the accepted laws and theories of the sciences. In his pioneering study, `Über Gestaltqualitäten', Christian von Ehrenfels first directed the attention of psychologists to instances of perceptual properties of objects which are characteristic attributes of wholes in the sense considered in this section--the so-called Gestaltqualitäten. It is to this end that the first condition for wholes given by von Ehrenfels is directed--the so-called First Ehrenfelscriterion, i.e. the condition that: `The whole is more than the sum of its parts.'» [Gestalt 94]


Scientific/Ontologic Levels (Strata) - Where New System Properties Emerge

[MB4 45, emphasis added] «All concrete systems are physical entities, in that they possess energy - a measure of changeability . However, some concrete systems are more than just physical entities, in the sense that the categories of physics are insufficient to account for them. For example, some are social systems. And altough some of the concepts of physics - in particular the notion of engergy - are necessary to acocount for any society, most are unnecessary. On the other hand social science requires new concepts, such as those of artifact, social group, justice, and culture. The peculiar concepts of social science are supposed to represent emergent properties of a society, i.e. properties that are not possessed by its components. Likewise the study of the components of any society, i.e. social animals, calls for a number of distinctly biological catetgories, such as reproduction, sex, and death. And if the animals happen to have a highley evolved nervous sys, we shall need still other categories, such as the concepts of altruims and planning, which are usually regarded as psychological. Finally, organisms are composed of chemical systems, which are physical entities of a very special kind, namely composed of atoms and molecules engaged in chemical reactions.
Thus the totality of concrete entities may be grouped into five genera:»
  1. physical things
  2. chemical systems: chemosystems + biochemosystems
  3. biosystems: biosystems (cells, organs, organisms) + psychosystems
  4. sociosystems
  5. artifical things

Emerging properies may be sortals, i.e., give raise to new identity criteria. Different identity criteria are another way of defining the ontological levels (strata) of (concrete) particulars [OntPrinc]:
levelexampleindividuationpersistence
extensional atomica minimal grain of matter minimal spatial or temporal dimensionsspatio-temporal continuity
statica configuration of atoms, a situation mereological sum of atomsunchanged non-temporal properties
mereologicalan amount of matter (possibly disconnected) mereological sum of entitiessame parts
physical topologicala piece of matter self-connectionsimilar topology
morphologicala cubic block proximity similar spatial shape / temporal pattern
based on interaction with external world functionalan artifact purposepersistence of functionality
biologicala human body presence of lifepersistence of life
intentionala person or a robot intentional behaviorpersistence of (capability to) intentional behavior
sociala company inter-agent connections (rules, conventions)persistence of inter-agent connections
Note: an amount of matter and a piece of matter are two distinct entities, «since a piece of matter can cease to exist (generating new pieces), while the same amount of matter is still there.. A doughnut belongs to the same level, but with a more sophisticated [identity criterion], since its identity changes when the hole is destroyed while the dough remains self-connected» [OntPrinc].


More Than Sum 3: Attribute Invariance under Structural Transformation

Structured whole. «These structural features of wholes are of interest because one important idea covered by the term `whole' is that of a structured orgranisation of elements. A structured whole in this sense involves three things: (1) its parts [G], (2) a domain of `positions' [X] which these parts `occupy' (this need not necessarily be spatial or temporal, but may have any kind of topological structure whatever), and (3) an assignment [f] specifying which part occupies each of the positions of the domain. A (particular) performance of a musical composition is the classical example of a whole [(X,G,f)] in this sense: the time-interval of the performance serves as the domain of positions [X], the various tones [G] (as characterisedby their pitch, volume, and duration) which are played throughout the performance are the parts, and the score [f] which fixes the distribution of these notes throughout the performance is the assignment» [Gestalt 100].

Complexes. «Now, in scientific discussion, we often do not know (or care) about the individual parts which occupy the various positions. An example from chemistry: when discussing the molecule H-O-H, it suffices that some O atom should occupy the place corresponding to the center space of the representation; it makes no difference in our discussion which particular oxygen atom this is. These considerations lead us to the concept of a complex. We will say that whenever any structured whole is considered with a view to the types of its parts, rather than its specific parts themselves, it is viewed as a complex» [Gestalt 100].
«A complex is characterised by the following three features:

  1. A set G of topologically structured attributes.
  2. A topologically structured space X, constituting the domain of positions.
  3. An assignment f of exactly one G-attribute to each X-position» [Gestalt 100].
«For the purpose of some disciplines, such as chemistry, it is of interest to distinguish two kinds of `decomposition' of a complex, each of which yields one of the two principal constituents: the set G of component-types, and the topologically structured space X. For example, if for a given molecule--say that of benzen--the structural arrangement of the constituent atoms is disregarded, there remains the `molecular formula', C6H6, which makes it indistinguishable from another quite dissimilar compound. If, on the other hand, the types of the atoms are disregarded, there remains the `structural formula', the hexagonal ring, which has itself interesting chemical attributes and may be occupied by other atoms than carbon» [Gestalt 101].

Isomorphism. «Two complexes (X1,G1,f1) and (X2,G2,f2) are isomorphic if

  1. X1 and X2 have the same topological structure,
  2. there exists a one-to-one correspondence F of G1 and G2 which preserves their type, and all of their topological properties, and
  3. the assignments fi assign F-corresponding Gi attributes to corresponding Xi positions.» [Gestalt 101f].
E.g. the musical transposition of a composition is isomorphic in this sense.
«[I]somorphism of complexes requires the existence of two mappings, an homeomorphism H: X1 <-> X2, and a topology-preserving 1-1 correspondence G: G1 <-> G2, which together satisfy the additional requirement that for any element (position) x of X1, F(f1(x)) = f2(H(x)); or abstractly, that f2 = F o f1 o H-1 ... If we term such an f2 a transposition of f1, it is readily seen that the set of all transpositions constitutes a group (in the algebraic sense), with respect to function composition as the group operator. ... a group of transformations ... [or, equivalently] the equivalence-set of the corresponding equivalence relation (i.e. transponibility)» [Gestalt 103].

Complexical Feature. Typical groups of isomorphisms preserve certain properties. «In the case of our musical example, the isomorphic complexes--transposed compositions--have a significant common structural characteristic, they have the same melody» [Gestalt 103]. «The musical composition (complex) has an attribute (is a melody) which is unchanged or invariant under transpositions belonging to a subgroup of the group of all abstractly possible transpositions (the transpositions in the sense of music).» [Gestalt 104].
«Given some subgroup Z of the group of all transpositions of a complex, we designate as a complexical feature (relative to Z) of this complex any attribute which it shares with all complexes differing from it only by Z-transpositions, i.e. any attribute invariant under these transpositions» [Gestalt 104].
«In the applications of this schematism of complex and isomorphism, it may happen that a complexical feature reflects an attribute of a complex which is underivable in the sense of our earlier discussion ... and this, consequently, is of special interest. ...
It should be remarked that the possession of such attributes, which are invariant under transpositions, is another condition for Gestalten, the so-called Second Ehrenfels-criterion ...» [Gestalt 104].

«An important application of these concepts is to cases in which something is constant under varying processes or modifications. For if the object in question can be represented as a complex in our sense, and its modifications as transpositions, the constancy will amount to a complexical feature. Significant instances in the applications are furnished by physical systems that attain a state which is indepdendent of time, a stationary state or state of equilibrium: a state left invariant by the processes of nature. ... An object is considered a good Gestalt in the degree to which it exhibits invariance or stability ...
... Thus in the case of the Gestalten of visual perception, a premium is put on symmetry, simplicity of linear structure, and unifomity of component structures, since all of these lead to invariances under certain groups of geometric transpositions.» [Gestalt 105f]


Ulf Schünemann 111201, 301202