Anna-Mari Rusanen Department of Philosophy, History, Culture and Art Studies University of Helsinki Department of Physics University of Helsinki

 There are hundreds (thousands?) studies, which indicates the process of conceptual change is one of the key charasteristics of science learning  Even within the devoted literature on conceptual change, there is no agreement on how to explain conceptual change

 By conceptual change cognitive scientists and cognitive psychologists mean (roughly) a specific kind of learning process:  a student does not merely accumulate more knowledge,  but her conceptions of phenomena in a certain domain undergo a restructuring process  that affects ontological commitments, inferential relations, and standards of explanation.

 can be characterized:  as transformation of the initial knowledge-state ( for example, a commonsense picture of the world) to one of various outcome knowledge states.  The outcome:  a scientific conception (when the learning process has been successful)  or one of a number of unscientific misconceptions (when it has not). State 1  State 2

 There are different forms of conceptual change, for example: 1)Revision: In some cases cc requires a revision of existing conceptual system  For example: ▪ Category shifts (Chi) ▪ Tree jumping (Thagard) ▪ Intergration of a conceptual system (diSessa)

2) Reinterpretation: In some cases cc requires that a learner gives a new interpretation for the existing concepts/conceptual system  For example: ▪ Resubsumption (Ohlsson) ▪ Differentiation and coalescence (Carey)

3) Invention: In some cases cc requires construction or production of novel conceptual systems  Even in a way that makes the new and old systems ”incommensurable” (Carey)  For example: bootstrapping 4) And so on…

 Typically involves: 1) analysing/characterizing the specific cognitive task (=information processing task) being performed by a system 2) describing how a certain cognitive mechanism executes/produces/sustains the phenomenon ▪ Often requires the decomposition of a complex mechanisms into simpler ones ▪ Is typically given by specifying the precise algorithms 3) describing, how the mechanism is implemented Input  Outco me

The description for the task is given by characterizing the information processing task:  What is the specific cognitive task (=information processing task) being performed by a system?  Why it needs to be performed? Input  Outco me TASK?

Input  Outco me The characterization of information processing task creates also some constraints for the possible underlying mechanisms:  Characterizes, why certain (but not all!) learning mechanism are appropriate for fulfilling the cognitive task. TASK

 not often clearly addressed in the literature, but many share the same intuition:  Reorganization of the conceptual system, which (in a case of succesful learning) for example ▪ Makes the system more fruitful, intelligible etc. (Posner & Strike) ▪ makes the conceptual system more useful (Ohlsson) ▪ integrates the piecemeal structure of a conceptual system, and makes the system more coherent (Disessa, Thagard) Input  ?

 How is the task executed/ performed?  How are the inputs and outputs represented in the mechanism?  How does the mechanism transform the input to generate the output (step by step )?  Often requires the decomposition of complex mechanism into simpler ones Input ? Outco me

 Several attempts to define, but broadly (Bechtel):  A mechanism is a structure performing a (information processing) function in  virtue of its components parts,  component operations,  and their organization.  A description of a mechanism should describe this organisation in a detail

 Many suggestions for the cognitive ”mechanisms” of conceptual change  Many characterizations for the task; many suggestions for the mechanisms  Two major category:  Revision- mechanisms: Mechanisms underlying conceptual change revise the conceptual system by changing its conceptual organisation  Production of new concepts: Mechanisms underlying conceptual change produce novel concepts/conceptual systems

”MECHANISMS” of CONCEPTUAL CHANGE REVISION by assimilation & accomodation (Vosniadou) resubsumption (Ohlsson) integration & reorganisation (diSessa) Category shifting & recategorisation (Chi) Differentiation and Coalescence (Carey) PRODUCTION of new concepts by Concept combination (with combinatorial syntax) Bootstrapping (Carey)

 Often the descriptions of these ”mechanisms of conceptual change” are quite shallow and offer no information about the precise structure of mechanisms/how they work  For example, Chi et al:  ”Conceptual change is the process of removing misconceptions… (which) are, in fact, miscategorizations of concepts”  and so ”conceptual change is merely a process of reassigning or shifting a miscategorized concept from one category to another”

 Chi: By assimilation (=adding new information) and recategorization  What is categorizing/ recategorization?  “[c]ategorizing is the process of identifying or assigning a concept to category to which it belongs“ (Chi 2008, 62).  Chi offers no description, how these identifyings/assignings are supposed to happen State 1  State 2 Recategorization The description ?

 If the structure of a mechanism is not specified, a description offers (at its best) a sketch for a possible mechanism, not a suggestion for an explanatory mechanism  An explanatory model of a mechanism requires a sufficiently detailed and accurate description (Bechtel MDC, 2000; Craver, 2006/2007)

 When the details of these mechanisms (reorganisation, bootstrapping, resubsumption, category shifts, etc.) is analyzed:  they are often just collections of some more basic cognitive mechanisms, which are ultimately responsible for the conceptual change: ▪ Categorization, mapping, transfer, assimilation, accomodation, analogical reasoning, inductive inference, abduction…

 Imagine, you´d have to learn a novel concept ”Cognitive architecture”  How do you learn it?  Carey: by building a model of the target  How do you do it?  A learning mechanism: By bootstrapping i.e. by using some of your existing concepts to build a new concept

1) Initial State:  occurs when a learner encounters a set of interrelated explicit symbols, such as symbols of a scientific theory  ”Cognitive architecture, compositionality, information semantics, representation…”  These symbols, ”PLACEHOLDERS”, are uninterpreted:  Are partially mapped/not mapped into any already existing concepts

2) The process of conceptual change: These placeholders are then taken up by various ”modeling processes”, which include  Inductive reasoning, analogical reasoning, abduction etc.  If you know something about models in physics, you might think that the structure of ”cognitive architecture” is analogical  These cognitive processes ”produce” the content for placeholders

3) The Outcome:  When these placeholder symbols have a stable conceptual role in a new structure, they have a conceptual content in virtue of their conceptual role  The new structure may be incommensurable with the old one

 When ”bootstrapping” is given a description, it turns out to be a collection of some more ”basic” mechanisms:  Mental modeling (?), analogical reasoning, inductive reasoning, abduction, etc.

 Ohlsson describes the process of resubsumption:  Conceptual change happens, when a person uses analogical transfer to map conceptual system from one domain A to a new domain B, which has been earlier conceptualized by another system  If the new system is evaluated to be more useful, the target domain is reinterpreted by it  The mechanisms: analogy, transfer, mapping, interpretation…

 There is evidence that for example analogical reasoning (and transfer) play a crucial role in some forms of conceptual change  BUT: not much is known, how, for example, analogical reasoning should be understood in the context of complex learning in adults (Markman)

 In addition, from the cognitive point of view, analogical reasoning is a complex process, and may involve several other mechanisms:  Similarity comparisons, visuo-spatial mechanisms for imagination, mechanisms for mapping from one system to another…  These mechanisms may involve several submechanisms ▪ there is evidence that even some motor control- mechanisms are used in some sort of mappings (number learning in childhood…?)

 Requires that the mechanisms responsible for a certain type of conceptual change should be specified in a detail  Can be really challenging in the case of conceptual change, because it may involve a hierarchical collection of many different submechanisms  Some of those are better ”known” (categorization, inductive reasoning), some of those aren´t (mapping mechanisms?)

 In addition, there are many different forms of conceptual change, and they may involve several different mechanisms  Ohlsson, 2009: A theory of cc cannot just be the list of all possible mechanisms, it must also constraint mechanisms  It must be able to tell, why certain mechanisms are appropriate for cc, and why some other aren´t  For this reason, the task level also matters

 From a cognitive science point of view, explaining conceptual change requires: 1) A precise description for the information processing task 2) A sufficiently accurate and detailed description of the mechanisms responsible for the task  can be a really challenging task!

 But why to bother? Do we really need to know?  Yes:  If you do not know, how it works, you do not know, how to manipulate it  If you do not know, how to manipulate it, you don´t know, how to facilitate it