Probably the significance of this article is due to fact that it provides a potential answer to the “what else could it be” argument, since the goal of the author is to propose a viable alternative to the computational paradigm in cognitive science (346, 359). According to this alternative, cognitive systems may be dynamical systems[AM1] . One of the most relevant features (if not the most) of this view is that, in contrast with orthodox-computational cognitive science, it eliminates representations -more precisely: at least certain kinds of systems are better understood excluding any reference to representations-.
The core of the argument deal with a device –called governor- of which purpose is to regulate steam power. This devise can be describe either in computational terms, that is, in form of an algorithm involving the manipulation of symbolic representations, or in a non-representational way, which coincides –this is a good rhetorical effect- with the actual solution to the problem, namely, the actual device built by James Watt.
The relation between certain parts of the device, the arm angle and the engine speed, is a key factor in the machine operation. According to the author this relation is a particular kind of dependence, which is non-representational. In fact, in order to describe such interaction a more powerful conceptual framework is needed, this framework is the mathematical language of dynamics. The relevant suggestion whit regard to our course is that “Cognitive systems may in fact be dynamical systems, and cognition the behaviour of some (non-computational) dynamical system” (358). The crucial point is how to establish “the bridge”, that is, the relevant relationship, between the Watt device and the human cognition. This connection is provided by the motivational oscillatory theory (MOT) (361) [It is difficult for me to follow the mathematical explanation], mainly because “In MOT, cognition is not the manipulation of symbols, but rather state-space[A2] evolution in a dynamical system” (362). (MOT is a case within a more general dynamical framework called for some authors “decision field theory”).
As far as I understand the argument the key feature is expressed in this sentence: “And it would be a model in which the agent and the choice environment, like the governor and the engine, are tightly interlocked” (360).
CONSEQUENCES REGARDING EMBODIED COGNITION
We can call this point “The autonomy question”: To what extent is the brain autonomous or self-contained regarding cognition? This is a significant issue in the Gursh reply. Van Gelder[AM3] , indicates that given that according to the computational view “the cognitive system traffics only in symbolic representation, human body and the physical environment can be dropped from consideration; it is possible to study the cognitive system as an autonomous, bodiless, and worldless system whose function is to transform imput representation into output representations” (373). Conversely, for the dynamical conception “the cognitive system is not just the encapsulated brain; rather, since the nervous system, body, and the environment are all constantly changing and simultaneously influencing each other, THE TRUE COGNITIVE SYSTEM IS A SINGLE UNIFIED SYSTEM EMBRACING ALL THREE” (373, see also 379).
(This is an expression of the continuous, simultaneous and mutually determining change which characterizes a dynamical system).
Another argument, among others, for the biological plausibility of this model concerns time. The role of time is more explicit and relevant in dynamics than in computational models, and “Timing is critical to a system that operates in a real body and environment” (379).
-Concerning the Cartesian assumptions considered by Grush, Van Gelder presents his notion of cognition as embodied and embedded in contrast to the Cartesian view and in concordance with the anti-Cartesian movement. In this sense, the dynamical account of cognition may be understood as a post-Cartesian approach to the mind and to the nature of the human being (see 380-381).
-Interesting remark: connectionist models are only a particular subcategory of dynamical systems. The kind of dynamical models suggested by the author for the cognitive system are different from connectionist model (see 370, 371)
SOME QUESTIONS
-In these two articles the notion of representation plays a significant role, I find that a potentially problematic aspect of the nature of representation is the relation between representation and symbol. Van Gelder talks of “symbolic representation” (350, 353), in a sense in which is difficult to distinguish between symbol and representation. Is every representation symbolic? On the other hand, the representational function appears to be a necessary element in the definition of symbol.
-When the author describes the computational model, he recalls that computation implies to manipulate symbols, and points out, that these symbols “have meaning” (350). Does this mean that the machine (the device or its parts) work with semantic properties?
-According to Van Gelder if a system is not representational then it is not computational. Can be possible computation without representation? On the other hand, the author suggests the possibility that a dynamical system incorporates representations within a non-computational framework (376, 377).
-“The computer does not realize the abstract dynamical model; rather, it simulates it” (369). What is the difference between realization and simulation?
-Finally, What is the strongest argument to claim that human cognition is a dynamical system?
[AM1]Dynamical systems are defined “as state-dependent systems whose states are numerical (in the abstract case, these will be numbers, vectors, etc.; in the concrete case, numerically mensurable quantities) and whose rule of evolution specifies sequences of such numerical states” (368).
[A2]the notion of state-space: The concept of state-dependent system: “A (concrete) state-dependent system Is a ser of features or aspects of the world which change over time interdependently…” (363).
FURTHER QUESTIONS ABOUT DYNAMICAL SYSTEMS:
The mathematical nature of dynamical systems (“in the concrete case, numerically measurable quantities” -368-) arises some questions:
-It is possible to account for consciousness by means of a set of equations?
-Is this model compatible with the free will?
Can this model account for the “interface problem” (the relationship between personal and subpersonal levels?
-Does follow –obey- both the brain and the mind –that is, physical and mental properties- the same equations?
-If the operation of the mind is capable of being expressed in a set of equations does entail the existence (and the identification) of psychological laws?
-To what extent criticism over the crucial example of dynamical research on human decision making (basically MOT) can affect to the whole theory regarding cognitive science?
One important point in this sense could be: MOT is characterised in this way: “The framework thus includes variables for the current state of motivation, satiation, preference, and action (movement), and set of differential equations describe how these variables change over time as a function of the current state of the system” (361).
How the variables are identified and picked up (chosen)? And how the numerical value is assigned to every variable? I think that this is a crucial problem since the model does not provide an answer and given that it is critical en the final result. Similarly, to contemplate an entire cognitive system (not just a particular task, skill or behaviour), for example the brain-body-environment system, or merely the mind-brain system, as a dynamical system arises the same questions.
[AM1]Dynamical systems are defined “as state-dependent systems whose states are numerical (in the abstract case, these will be numbers, vectors, etc.; in the concrete case, numerically mensurable quantities) and whose rule of evolution specifies sequences of such numerical states” (368).
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