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Explanation of cognition in Cognitive Science
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Vizite: ? Nota: ? Ce reprezinta? Intrebari si raspunsuri
A review of Vacariu et al's explanation of cognition involved in "Toward a very idea of representation"

ABSTRACT. In this article I reproduce and examine some aspects of Vacariu et al explanation of cognition. I conclude that their explanation of cognition is not a complete one. I try to propose some alternative explanations toward a complete explanation of every posible cognition and to emphasize that the task of philosophy, as discipline included in Cognitive Science, is to find the necessary and sufficient conditions of every posible cognition. In final, I try to criticize the idea that cognition can be only representational.

There is a cognitive arhitecture with a hierarchy of levels of existence. Vacariu et al has considered that cognition cannot be explanated by a single level. Arguments:
-the emergency of the primitives of one level from the primitives of previous level.
- bidirectionality of cognitive processes; bidirectionality, wich is for Vacariu et al one of the most important ideas, is the continuous circular causation wich exist between conceptual and neural levels: the changes wich appear at the conceptual level involve changes at neural level and vice-versa.

Because of bidirectionality it is imposible to be explanated cognition using a single level, either by conceptual level like Fodor or by neural level as Churchlands.
But as has been sad previous, there is a cognitive arhitecture, and the conceptual level must to belong to its levels of existence, not to some metaphysical level. In the case of human cognitive arhitecture what is the diference between neural and conceptual levels ? In this case CNS must to be seen in levels. Its lower neuronal level maybe is the singular neuron level. Than, conceptual level must be situated, in acord with Vacariu et al, at higher level of compositionality and activity. But, there is no clear evidence that Churchlands would be reduced the conceptual level until at the singular neuron level.

The level of description that is proper to symbolic paradigm is conceptual: descriptive entities are simultaneous semantic symbols(they refers to external objects) and syntactical symbols(operations on the representations are manipulations of symbols). The level of description that is proper to conectionist paradigm(cf.Smolensky) is subconceptual: its descriptive entities are caled subsymbols because they are the constituents of the symbols proper to symbolic paradigm. However, operations are considered differently: subsymbols are manipulated by numerical computations(vectorial additions in a vectorial space of activation). Vacariu et al noted that maybe in one day, Churchlands eliminativism, wich reduce the conceptual level at the neural level, will win; but, the neural level can be eliminated in the favour of cuantic level. Fodor and Phylysyn consider that conceptual level cannnot be reduced at the neural level, because of representational character of mental symbols.The representational character of mental symbols is an argument against the reductionist program of theoretical unity of science(Fodor and Phylysyn, 1988). I think that, there must be a mereologycal dependence between levels and between the primitives at the every level. But, this dependece does not mean necesarly that the events from a higeher level emerge as mereological sums of the events from the lower levels."Organization is a property wich cannot be reduced to the properties of its parts, for the behavior of each part depends on those of the others and on the aims of the whole"(Del Re, 1998). For exemple, if we take one thousand of resistors and we try to conect them in all posibile structures, we know that there is only one structure, wich is total serial, in wich the total resistance, the event from higher level, is the individual resistors resistances sum, or the mereological sum of lower level events properties, but in structures that involve paralel connected resistors, the total resistance is not a simple sum of individual resistors resistance. As a kind of conclusion, human neurons are not miniatural human brains.

At each level of analysis/explanation there are some primitives. At the conceptual level the primitives are symbolic representations wich are static and discrete. Contraparts of symbolic representations at the neural level are the neurons activation paterns, but the corespondence between the primitives of conceptual level and those of neural level is not biunivoc. "...the structures from the 'higher levels' of sistem are rarely isomorphic, or even similar, to the structures of 'lower levels' of sistem"( Fodor and Pylysyn 1988, 63). Activations paterns are in permanent motion and change. At the subconceptual level the primitives are subsimbolic representations, and their content depend on the network's processing capacities and on the environment in wich it operate.

The relation between conceptual and neural levels

Merzenich and deCharms speaking about neural representations, affirm that there is a representational perceptual costancy even at the neural level, the activation pattern of the ensemble of neurons---from wich emerge the perceptual representation--- is in continuos motion and change." Representational relations between neural elements of a grup can be isomorphic over the changes of activation patterns ... and therefore they can realize representational constancy"(Merzenich and deCarms 1996,66). Extending this idea Vacariu et al considered that at the conceptual level we can speak of a representational constancy even if the ensemble of neurons that corespond to it are in continuous changing. Representations of conceptual level approximates the processes from the neural level; the stability from conceptual level is the result of this approximation. But I think that this stability about wich discuss Vacariu et al is a relative one; it is rather a question of speed of motion, at least at the level of the flux of thoughts; even at level of contents of single concepts there are sometimes historical changes. However, Vacariu et al' stability is relative to some lower faster changes. The rate of changes of those two flux of changes is different.

The changes at neural level are continuos, but there is a threshold of changing; when this threshold is exceeded some modifications of representations from the conceptual level appear. For exemple, in connectionism, excitation or inhibition of a knot depend on the signals wich are recepted from other knots; and, there is a threshold of the activation function. If the value of a recepted signal is biger than the value of threshlod function than the knot is activated, if no it is inhibated. The activation state of a unity is determined by the total input of this unity, relation between knots being more important than unities taken separately. Vacariu et al consider that our cognitive sistem and even our senses are determined by the our ecological recess. For exemple, our body have the ability to feel a certain scale of frequences when it is subjected to some repeted touch on a hand. Under a threshold, touch seem to be discrete. Over this threshold, they appear continuos. Relative to our cognitive sistem, crossing from one level of distinctions(continuity-discontinuity, static-in motion, stability-variability) to other one is duet by exceeding a threshold determinated by our ecological recess. However, at the conceptual level we can speak about a similarity interval in wich structures, states, processes( inteligible as approximations of structures, states and processes from the neural level) appear as identical, even if their neural activation patterns are different. Speaking about this interval of similarity, also, we should to take in consideration to type of changes: one at the neural level, and other from environment: when the changes of activation paterns exceed a certain threshold, some change appear at the conceptual level, and when the environmental changes attain a certain threshold, we can distinguish them sensorialy.

Human beings, as cognitive sistems, are open complex sistems, organized in many levels. In acord with many authors, consider Vacariu et al, behaviour is a self-organizing macroscopic structure wich appear as a result of interactions between micro and macro scales of organization. Or as it is put by Keijer, "behaviour is a multiple-scalar phenomenon, involving the patterns of a variety of scales of organization, is the result of interaction between pre-existing orders from this sistems and consist in reciprocal modulation of neural, bodily and environmental dinamics"(Keijer 1997, 204). Or more simply, behaviour is the result of dinamical interaction between body, brain and environment.

Vacariu et al consider that "cognition the result of multiple interactions between the levels of organism, and between every level and environment."

Now, we should to question us if this explanations are complet or sufficient.
If this explanations explain also human aging or digestion? What are the sense of those interactions? What are their function? What are their utility? What are the contents of those intercations? What are epistemological and gnoseological value? These explanations are only mechanical.

I consider that, this explanations are why-explanations, because they use the phrase 'result'. Jane Fay considered that, "every explanatory practice must be understooded in the frame of a question-answer speech. ... why-questions are not the only type of questions wich are put in science. However, I take explanation as being every answer wich carry relevant information as an answer to every question exccept if-questions"(Jan Faye 1999). Other complementary questions wich offer alternative explanations are what-questions, when-questions, where-questions, how-questions, for what-questions. Neither all the body-environment interactions(for, exemple ROS in aging) nor all the interactions from organism(for exemple, the senectogen influence of psychical stress) are cognitive. If we want to explain cognition, we must not only to synthetize the explanations offered by the main explanatory paradigms from cognitive science but also to lead towards a complete explanation of cognition, by offering the following types of explanations, synthetized by Faye:

1. Causal Explanation wich appeal to the real cause of certain phenomenon.
2. Nomical Explanation wich refer to the law of some phenomenon.

3. Functionalist Explanation wich refer to the real efect of some phenomen, in the sense that a certain phenomenon is favorable or suitable for reproduction or succesion of some individ or society.
4. Functional Explanation appeal at the real efect, but in sense that a certain phenomenon is favorable for survival or cohesion of an individ or society.
5. Intentional Explanation appeal at the intentioned efect of certain phenomenon by refering to the literal sense of certain human action.
6. Interpretative Explanation appeal at the conscious or inconscious intentioned efect of certain phenomen by refering to some metaphorical sense of some human action, text, symbol.

I think that, a complet/integral understanding of cognition must to offer a conjunction of the previous types of explanations. And this is compatible with Cognitive Science wich is multidisciplinary domain. We must to try to explain not only the human cognition or its artificial simulations but every posible cognition. We must to find the necesary and sufficient conditions of every posible cognition, not only of terestrial or of living things cognition. Every cognitive arhitecture have some properties wich depend on its unicity, and therefore they connot be reproduced, they should not preocupate us.

On the other hand, a concept is not any stable representation. Representations must to represent something, perceptions or experiences. The condition of posibility of something to be a representation is it to be in a representational relation with something that is representated. Now, a representation cannot refer to world directly, it refer to perception or to experience/experiences. Only sensors refer to the world directly. But, a representation must to be a re-presentation. A concept is a general notion; or an abstract representation; it is not just a stable representation. A first order concept must to be a general or abstract representation of a set of perceptions or feelings or direct experiences. A second order concept is a representation that is more abstract or general than an abstract representation wich corespond to a first order concept. A concept must to contain a minimal non-nul content. Therefore the stability of a representation is not a sufficient condition for something to be a concept.

A representation is any informational conscious content that is not of first order, that is perceptual content or first order feelings. In this sense memories are representations.

There cannot be a representation of future, because the future cannot be re-presented. There can be informational conscious contents wich try to anticipate the future state of the world. When we create something new existent we do not re-present anything. If there can be a cognition of a posible that never existed before, there its imagination, either abstract or concret, is not a re-presentation. In the base of scientific laws we can imagine the the future behaviour of some asteroids. We try to process all the human experience and memory to understand univers and to predict its future states, and for survival.

Other interpretation of the concept of representation is that in conformity with wich a representation is a state of brain wich is about something: about the the world or about some part/parts of it. But this interpretation is too extended, because all experience is in relation with world. Every sensorial experience is about some physical, chemical, biological stimulus. But sensorial experience is direct, not a re-presentation. A re-presentation must to be a meta-information; it must to refer to some conscious first order information/content. A conscious content/information can to be about some experiences from the past, but it can be also an anticipation not of the future states of the world but of the future perceptions of the world, in this sense it is not refer to something from the past, it is not a re-presentation. I tried to argument that not every mental content is re-presentational. Re-presentations had been too extended interpretated.

Appear the folowing question: can we talk legitimate about a reduction of re-presentations to memories?

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