Randall Beer wrote in his 2000 paper: "Although the three models reviewed here vary considerably in their details, they all share a focus on the unfolding trajectory of a system's state and the internal and external forces that shape this trajectory rather than the representational content of its constituent states or the underlying physical mechanisms that instantiate the dynamics. In some work, this dynamical viewpoint is augmented with a situated and embodied perspective on cognition, forming a promising unified theoretical framework for cognitive science broadly construed." More kinds of dynamical system I suspect that Beer and others are mostly thinking about what I have called "Atomic State Dynamical systems" (Sloman 1993), in contrast with "Molecular state dynamical systems" See "The mind as a control system," http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#18We need new kinds of dynamical system
This contrasts with
- composed of multiple smaller multi-stable dynamical systems, changing concurrently
- that can be turned on and off as needed,
- some with only discrete attractors, others capable of changing continuously,
- many of them inert or disabled most of the time, but capable of being turned on or off (sometimes very quickly)
- each capable of being influenced by other sub-systems or sensory input or current goals, i.e. turned on, then kicked into new states bottom up or top down,
- constrained in parallel by many other multi-stable sub-systems
- with mechanisms for interpreting configurations of subsystem-states as representing scene structures and affordances, and changing configurations as representing processes
- where the whole system is capable of growing new sub-systems, permanent or temporary, and short-term (for the current environment) or long term (when learning to perceive new things).
- where some of the subsystems are decoupled from the environment, and possibly even temporarily decoupled from other subsystems.
- where some of the semantic content refers to remote, or inaccessible, or past or future states, processes, etc. or even to mere possibilities. (Using "exo-somatic" ontologies.)
- Dynamical systems with a fixed number of variables that change continuously
- Dynamical systems with one global state (atomic state dynamical systems, as opposed to molecular state dynamical systems)
- Dynamical systems that can only be in one attractor at a time
- Dynamical systems with a fixed structure (e.g. a fixed size vector or tree).
- Dynamical systems tightly coupled with the environment.
- Dynamical systems whose only semantic contents refer to sensorimotor patterns. (Using "somatic" ontologies.)Vision is a process involving multiple concurrent simulations at different levels of abstraction in (partial) registration with one another and sometimes (when appropriate) in registration with visual sensory data and/or motor signals. The information is processed in different ways for different purposes, at the same time using different forms of representation.
Red lines indicate references to remote or inaccessible parts of the environment. Contrast "online cognition" and "offline cognition". NOTE ADDED 10 Aug 2012: An incomplete, but hopefully slowly growing attempt to be more systematic about these ideas is here: http://www.cs.bham.ac.uk/research/projects/cogaff/misc/kinds-of-dynamical-system.html
Randall D. Beer, 2000, Dynamical approaches to cognitive science, Trends in Cognitive Sciences, 4, 3, pp. 91--99, http://vorlon.case.edu/~beer/Papers/TICS.pdf Murray P. Shanahan Embodiment and the inner life: Cognition and Consciousness in the Space of Possible Minds, 2010, OUP, Oxford, Aaron Sloman, The Computer Revolution in Philosophy: Philosophy, Science and Models of Mind, Harvester Press (and Humanities Press) 1978, Hassocks, Sussex, http://www.cs.bham.ac.uk/research/cogaff/crp [Chapter 6 is particularly relevant] Aaron Sloman, The mind as a control system, In Philosophy and the Cognitive Sciences, Eds. C. Hookway and D. Peterson, pp. 69--110, Cambridge University Press, 1993, http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#18 T. van Gelder The dynamical hypothesis in cognitive science Behavioral and Brain Sciences, 21, 5, 1998,
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