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Evolution of Evolution of Complex Complex SystemsSystems
Lecture 11: Advanced Lecture 11: Advanced conceptsconcepts
Peter Andras / Bruce CharltonPeter Andras / Bruce Charlton
[email protected]@ncl.ac.uk
[email protected]@ncl.ac.uk
2
ObjectivesObjectives
Limits of expression of Limits of expression of communicationscommunications
Simplification and expansionSimplification and expansion Structures and institutesStructures and institutes Professional languagesProfessional languages Selection and competitionSelection and competition Interpenetration of systemsInterpenetration of systems EvolutionEvolution
3
Continuation distributionsContinuation distributions
E.g., human languageE.g., human language Formalism:Formalism:
)()(
)()(),(
)(,:
)()(
))(|(
,
xTxR
xTzxTyyTz
xTyyxorderTemporal
ionscommunicatotherreferencesofsetxR
ondistributioncontinuatixRxP
x
ioncommunicatxsetsymbol
4
Random eventsRandom events
Example: random spikes / Example: random spikes / spontaneous spikesspontaneous spikes
))(|(
,)(*
**
xTxPgeneralin
tionsimplificaxpxP
5
Meaningless Meaningless communicationscommunications
Not following the rulesNot following the rules E.g.,:E.g.,:
Random communicationsRandom communications Zero likelihood communicationsZero likelihood communications
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Limited length Limited length communicationscommunications
How long can be a sequence / pattern How long can be a sequence / pattern of referencing communications that of referencing communications that does not appear as random ?does not appear as random ?
n
iiinn
nn
pxRxPxRxRxxP
xxx
1
*11
11
))(|())(,),(|,,(
,,,
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Expressivity of a system Expressivity of a system languagelanguage
Richer symbol sets imply shorter Richer symbol sets imply shorter reference sequencesreference sequences
Trade-off between symbol set richness Trade-off between symbol set richness and the length of referentially and the length of referentially interlinked communication sequencesinterlinked communication sequences
*)1(1))(|(
)(),(
pnxRxP
nxxx
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Simplification of languages Simplification of languages – 1 – 1
E.g., E.g., Neurons: graded potentials / spikesNeurons: graded potentials / spikes Brain: diverse cortex structure / Brain: diverse cortex structure /
crystalline cortex structurecrystalline cortex structure Language: rich culture / simple Language: rich culture / simple
cultureculture
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Simplification of languages Simplification of languages – 2 – 2
Smaller symbol Smaller symbol setssets
))'(|'())(|(
)'()(
xRxPxRxP
xx
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Expansion of the languageExpansion of the language
Longer possible sequencesLonger possible sequences Increased informational contents – Increased informational contents –
better description of the system / better description of the system / environmentenvironment
))'(|'())(|( xRxPxRxP
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Memory and expansionMemory and expansion
Memory facilitates expansion by Memory facilitates expansion by allowing direct reference to earlier allowing direct reference to earlier communicationscommunications
Direct reference increases the Direct reference increases the likelihood of generating likelihood of generating continuation communicationscontinuation communications
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Information subsystem and Information subsystem and expansionexpansion
Information subsystem = processing of Information subsystem = processing of memories, generating new memories memories, generating new memories identity definition, checking and identity definition, checking and enforcement communicationsenforcement communications
Processing memories = combination of Processing memories = combination of memories memories simpler referencing of simpler referencing of combinations of memoriescombinations of memories
better self/environment descriptionbetter self/environment description
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Structure of Structure of communicationscommunications
Grammar in human languageGrammar in human language Courtship behaviour rules in Courtship behaviour rules in
animalsanimals Structuring the brainStructuring the brain
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StructureStructure
Restrictions on the Restrictions on the communicationscommunications
Structure makes sharper the Structure makes sharper the continuation distribution, e.g., by continuation distribution, e.g., by eliminating some possible eliminating some possible continuationscontinuations
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Specialist communicationSpecialist communication
Follows restrictive structural rulesFollows restrictive structural rules E.g., science, legal E.g., science, legal
communicationscommunications
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Expansion by specialist Expansion by specialist communicationscommunications
The possible continuation The possible continuation communications are reduced in communications are reduced in numbernumber
P(x|R(x)) increasesP(x|R(x)) increases Longer referential sequences are Longer referential sequences are
possible possible expansion of the expansion of the communication systemcommunication system
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Structure and Structure and specialisationspecialisation
Structure induces simplicity in Structure induces simplicity in communications and may lead to communications and may lead to the emergence of specialist the emergence of specialist communicationscommunications
Specialist communications induce Specialist communications induce expansion of the communications expansion of the communications systemsystem
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Institutions – 1 Institutions – 1
E.g., E.g., Courtship, marriageCourtship, marriage Parliament, cerebellum, Golgi Parliament, cerebellum, Golgi
organelleorganelle
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Institutions – 2 Institutions – 2
Institution: large set of coherent Institution: large set of coherent rules imposing structurerules imposing structure
The structural rules imply the The structural rules imply the constitution of a subsystem of the constitution of a subsystem of the communication systemcommunication system
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Institutions – 3 Institutions – 3
By inducing a subsystem, By inducing a subsystem, institutions lead to the expansion institutions lead to the expansion of the communication systemof the communication system
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Professional language Professional language
E.g., legal languageE.g., legal language Specialist language in the context Specialist language in the context
of an institution systemof an institution system
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Professional institution Professional institution systemssystems
Professional language and Professional language and institution systeminstitution system
E.g., subsystems of modern societyE.g., subsystems of modern society
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Language code – 1 Language code – 1
E.g., legal system: E.g., legal system: legal / illegallegal / illegal
common / statute / commercial / penalcommon / statute / commercial / penal
Multilevel set of questions with few Multilevel set of questions with few possible answers that classify possible answers that classify communicationscommunications
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Language code – 2 Language code – 2
Professional languages with Professional languages with institution systemsinstitution systems
Multilevel simple answer questions Multilevel simple answer questions that classify the communications that classify the communications along the defining rules of the along the defining rules of the institution systeminstitution system
Language code Language code system identity system identity
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Binary codeBinary code Social sub-systems: professional institution Social sub-systems: professional institution
systemssystems Legal / illegal; power / no power; profit / no Legal / illegal; power / no power; profit / no
profitprofit Binary code: the top level coding that Binary code: the top level coding that
defines what communications are part of a defines what communications are part of a communication subsystem of the societycommunication subsystem of the society
If a communication can be referenced in If a communication can be referenced in such terms it fits into the subsystemsuch terms it fits into the subsystem
There are further levels for inner There are further levels for inner distinctionsdistinctions
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Environment of systemsEnvironment of systems
Environment: infinitely complexEnvironment: infinitely complex System: communications about System: communications about
itself – complementary model of itself – complementary model of the environmentthe environment
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System actions and System actions and perceptionsperceptions
System: model of the environmentSystem: model of the environment Communications: reference other Communications: reference other
communications and provide reference communications and provide reference for further communications for further communications maintain maintain the systemthe system
Communications lead to changes in the Communications lead to changes in the environment by changing the behaviour environment by changing the behaviour of communication unitsof communication units
Changes in the environment lead to Changes in the environment lead to changes in the system communications changes in the system communications providing the basis for system providing the basis for system perceptionsperceptions
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Predictive sustainabilityPredictive sustainability
The system is reproducible / sustainable if The system is reproducible / sustainable if the actions of it produce appropriate the actions of it produce appropriate changes in the environment to expand the changes in the environment to expand the systemsystem
Also, if perceptions lead to such appropriate Also, if perceptions lead to such appropriate actionsactions
In a sense the system’s description of the In a sense the system’s description of the environment allows good predictions about environment allows good predictions about the environment to reproduce and expand the environment to reproduce and expand the system the system predictive sustainability predictive sustainability
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Competing systemsCompeting systems Systems in the environmentSystems in the environment Each having predictions about the Each having predictions about the
environment using their actions and environment using their actions and perceptionsperceptions
Systems have different level of predictive Systems have different level of predictive sustainability depending on the sustainability depending on the environmentenvironment
Systems with better predictive Systems with better predictive sustainability attract communication units sustainability attract communication units to produce communications that are part of to produce communications that are part of the system easier than systems with less the system easier than systems with less predictive sustainabilitypredictive sustainability
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Selection of systemsSelection of systems
Systems in an environmentSystems in an environment Selection pressures: which system Selection pressures: which system
has better predictive sustainability has better predictive sustainability in the environmentin the environment
Systems with better predictive Systems with better predictive sustainability are selected by the sustainability are selected by the environmentenvironment
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Simplicity, memory, expansion, Simplicity, memory, expansion, selectionselection
Systems with memory can expand more Systems with memory can expand more than systems without memorythan systems without memory
Systems that undergo simplification and Systems that undergo simplification and expansion can capture a larger part of expansion can capture a larger part of the environmentthe environment
Longer descriptions make better Longer descriptions make better predictionspredictions
Better predictions make more likely Better predictions make more likely selection by environmentselection by environment
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Interacting systemsInteracting systems
Communication units produce Communication units produce communications that are part of communications that are part of systems (more than one)systems (more than one)
System communications have System communications have effect on communication units, effect on communication units, these affect the communications these affect the communications produced by communication units produced by communication units in other communication systemsin other communication systems
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The boundary of systemsThe boundary of systems
Communication units are not part of systemsCommunication units are not part of systems Systems are made up by communications Systems are made up by communications
between communication unitsbetween communication units Dense / rare communication density Dense / rare communication density
boundary in the sense of referencingboundary in the sense of referencing System communications may also reference System communications may also reference
communications which are not part of the communications which are not part of the system (these are part of other systems)system (these are part of other systems)
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Changing system Changing system boundariesboundaries
The number of references to The number of references to communications of several systems may communications of several systems may changechange
In this way the communications may In this way the communications may belong more to one system than to other belong more to one system than to other systemssystems
One system may dominate the One system may dominate the communications of a communication unit communications of a communication unit of which communications were dominated of which communications were dominated before by another systembefore by another system
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Interpenetrating systemsInterpenetrating systems Two systems using communications of an Two systems using communications of an
overlapping set of communication unitsoverlapping set of communication units System 1 communications influence System 1 communications influence
communication units inducing changes in communication units inducing changes in System 2; it works in both waysSystem 2; it works in both ways
System 2 communications reference System 2 communications reference sometimes System 1 communicationssometimes System 1 communications
Such references may follow System 1 Such references may follow System 1 referencing rules (i.e., continuation referencing rules (i.e., continuation distributions)distributions)
New continuation distributions may emerge in New continuation distributions may emerge in System 2System 2
E.g., Politics and educationE.g., Politics and education
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Dense communicationsDense communications
Dense cluster of communications Dense cluster of communications between communication unitsbetween communication units
Dense cluster in sense of Dense cluster in sense of referencing = system referencing = system
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Double contingency and Double contingency and systemssystems
Referencing to other system communicationsReferencing to other system communications Questioning the existence of the Questioning the existence of the
communication cluster – the system – communication cluster – the system – questioning the identity of the system (e.g., questioning the identity of the system (e.g., immune system)immune system)
This leads to the formation of rules and This leads to the formation of rules and sharpening of rules / continuation distributionssharpening of rules / continuation distributions
Subsystems as institution systems emerge Subsystems as institution systems emerge from a grouping of structure rules when the from a grouping of structure rules when the identity of the communication cluster is identity of the communication cluster is questioned questioned double contingency double contingency
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Interpenetration and Interpenetration and emergence of systemsemergence of systems
Systems interpenetrating Systems interpenetrating modifying each modifying each other’s communication continuation rulesother’s communication continuation rules
Communications referring to Communications referring to communications of both systems, new communications of both systems, new communications refer to these communications refer to these communicationscommunications
New dense referencing cluster may emergeNew dense referencing cluster may emerge Questioning the existence of the new Questioning the existence of the new
cluster leads to the expansion of the cluster cluster leads to the expansion of the cluster and formation of the specific rules / and formation of the specific rules / continuation distributions of the new system continuation distributions of the new system identity definition for the new system identity definition for the new system
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ExamplesExamples
Biology and mathematics Biology and mathematics theoretical biologytheoretical biology
Neuroscience and pharmacology Neuroscience and pharmacology neuro-pharmacologyneuro-pharmacology
Media and hospitals Media and hospitals health care health care PRPR
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Evolution of systems – 1 Evolution of systems – 1
Systems recreate and expand Systems recreate and expand themselvesthemselves
They interact with other systemsThey interact with other systems Changing their rulesChanging their rules Changing their boundariesChanging their boundaries Changing their identityChanging their identity
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Evolution of systems – 2Evolution of systems – 2
Systems develop structures Systems develop structures The structures may organize into The structures may organize into
institution subsystems by institution subsystems by questioning the identity of the questioning the identity of the subsystemsubsystem
This may lead to simplificationsThis may lead to simplifications Simplification trigger expansionSimplification trigger expansion
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Evolution of systems – 3Evolution of systems – 3
At the interface of systems new At the interface of systems new dense communication clusters may dense communication clusters may emergeemerge
By questioning the identity By questioning the identity (existence) of the new clusters (existence) of the new clusters new systems emergenew systems emerge
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Evolution of systems – 4Evolution of systems – 4
Systems compete for communications Systems compete for communications between communication unitsbetween communication units
Systems describe / predict the Systems describe / predict the environmentenvironment
Systems with better predictions have Systems with better predictions have better predictive sustainability, they are better predictive sustainability, they are selected under environmental selection selected under environmental selection pressures (they more easily reproduce and pressures (they more easily reproduce and expand than other systems with less expand than other systems with less predictive sustainability)predictive sustainability)
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Evolution of systems – Evolution of systems – SummarySummary
Systems recreate, expand and Systems recreate, expand and changechange
New systems and subsystems New systems and subsystems emergeemerge
Systems compete and some are Systems compete and some are selected under environmental selected under environmental selection pressuresselection pressures
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Summary – 1 Summary – 1
Length of communication referencesLength of communication references Simplification and expansionSimplification and expansion Structures, institutes and sub-systemsStructures, institutes and sub-systems Professional languages and binary Professional languages and binary
codecode Predictive sustainability and selectionPredictive sustainability and selection
46
Summary – 2 Summary – 2
Changing system boundariesChanging system boundaries Interpenetration of systemsInterpenetration of systems Double contingency and the Double contingency and the
emergence of systemsemergence of systems Evolution of systemsEvolution of systems
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Q&A – 1 Q&A – 1
1.1. Is it true that simplification of the Is it true that simplification of the communication symbol set leads to the communication symbol set leads to the expansion of the communication expansion of the communication system ?system ?
2.2. Is it true that structures are restrictions Is it true that structures are restrictions on the continuation distributions on the continuation distributions leading to the sharpening of them ?leading to the sharpening of them ?
3.3. Is it true that institutions are rule sets, Is it true that institutions are rule sets, which may organize into sub-systems ?which may organize into sub-systems ?
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Q&A – 2 Q&A – 2
4. Is it true that a professional language is 4. Is it true that a professional language is a subset of a system language a subset of a system language corresponding to an institution system ?corresponding to an institution system ?
5. Is it true that the language code defines 5. Is it true that the language code defines which communications are part of the which communications are part of the specialist language ?specialist language ?
6. Is it true that the political system is a 6. Is it true that the political system is a professional institution system of the professional institution system of the society ?society ?
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Q&A – 3 Q&A – 3
7. Is it true that professional institution systems 7. Is it true that professional institution systems of the society have a binary code ?of the society have a binary code ?
8. Is it true that system communications can be 8. Is it true that system communications can be viewed as predictions about the viewed as predictions about the environment ?environment ?
9. Is it true that a system’s ability to reproduce 9. Is it true that a system’s ability to reproduce and expand in an environment depends on and expand in an environment depends on the system’s predictive sustainability ?the system’s predictive sustainability ?
10. Is it true that selection pressures favour 10. Is it true that selection pressures favour systems with richer symbol sets ?systems with richer symbol sets ?
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Q&A – 4 Q&A – 4
11. Is it true that interpenetration means that 11. Is it true that interpenetration means that systems change their boundaries as a systems change their boundaries as a result of the interaction between the result of the interaction between the systems ?systems ?
12. Is it true that new systems always 12. Is it true that new systems always emerge at the interface of systems ?emerge at the interface of systems ?
13. Is it true that questioning the identity of a 13. Is it true that questioning the identity of a referential communication cluster leads to referential communication cluster leads to the formation of the corresponding the formation of the corresponding communication system ?communication system ?
