Pragmatic action (Kirsh and Maglio 1994) Task-performance is often described in terms of step-by-step progression through a range of states of the world to reach a goal state. The parameters of variation are defined, and the cognitive system --generates a representation of the way the world is --calculates the next move such that, when it’s taken, the physical world will be closer to the goal state --implements that move by generating an action The quality of an action is determined by the extent to which its effects bring the physical system closer to the goal state (winning a game, for example). Each such action counts as a pragmatic action.

Simple example: exit the room --Identify the door’s coordinates and one’s own coordinates --Minimize the distance between the two, one physical step at a time

More complicated example: Tower of Hanoi

Rules of ToH --Move all three disks from left to right, ending up with the same graduated configuration --Move only one disk at a time --A larger disk may never be on top of a smaller one Here, moving “closer to the goal” is defined in terms of a decision tree, moving closer to the action is to move the system further along a successful branch on the tree

Playing Tetris --Zoids fall from above --Buttons to rotate/drop --Zoids are rigid --If they stack up to top, game over --During the game, filled rows disappear

Playing Tetris: the orthodox cognitivist model of action generation

Problems with the orthodox approach Among other things, it doesn’t explain --the number of rotations --early rotation --translation (movement to the wall and back)

Kirsh and Maglio, p. 20 “If one’s theory of the agent assumes that thinking precedes action, and that, at best, action can lead one to re-evaluate one’s conclusions, then action can never be undertaken in order to alter the way cognition proceeds.” This, they claim, is misguided. Instead agents perform, epistemic actions, ways of altering the information available to the agent and thereby altering “the way cognition proceeds.”

C&C’s Three Ways to Play Tetris 1. Internal imagery only 2. Choice between use of internal imagery and external rotation 3. Choice between the use of internal imagery and use of internal rotation implant.

The moral There’s no principled difference between the external rotation process in case 2 and the implant’s processing in case 3. But there is no principled difference between the internal processes in cases 3 and 1. So, given that case 1 is clearly cognition, case 2 must be as well.

Clark and Chalmers’s Otto -Bad memory, so stores info in notebook -Entries in notebook guide action in the same way that memories (or nonoccurrent beliefs) stored in cortex do. -If Inga (the normal) has nonoccurrent beliefs stored in cortex, then Otto has nonoccurrent beliefs stored in his notebook (so his mind is extended beyond the boundary of his skin and skull).

At least three things going on --Attempt to break down internalist prejudice (what Clark sometimes calls ‘skin-bag prejudice). --A functionalist (or related computation- based) argument for extended minds. --Argument about the best way to do cognitive science

Parity Principle If, as we confront some task, a part of the world functions as a process which, were it done in the head, we would have no hesitation in recognizing as part of the cognitive process, then that part of the world is (so we claim) part of the cognitive process. (Clark and Chalmers, p. 8)

Doubts about the Parity Principle Doesn’t explain what makes something cognitive. Why should cognition be whatever strikes us as cognitive (if it’s in the head)? Worst of all, it gives the wrong answer in some cases. (Neuron on the table.)

Functionalism about mental states To be in a given mental state is to be in some (physical) state or other that plays the appropriate causal role, where causal roles are to be defined in terms of relations to inputs, outputs, and other mental states. But isn’t this circular, given the reference to other mental states?

Put formally (x){x is in mental state M if and only if  F1…  Fn[T(F1…Fn, I1…Im, O1…Ol) & Fix]} where the Is and Os are antecedently understood predicates, typically taken to express input and output properties, and where T(F1…Fn, I1…Im, O1…Ol) represents the best theory of the causal relations that obtain between mental properties and input- and output-properties (sensory inputs and behavioral outputs on most functionalist accounts of mental properties).

Realization (x){Fix if and only if  P1…  Pn[T(P1…Pn, I1…In, O1…On) & Pix]} Where Ps denote physical properties. In other words, given a theory of how the mental states are related to each other (and to inputs and outputs), whether something is in one of those mental states is determined by the presence of a corresponding pattern of interrelated physical states.

Clark and Chalmers’s Functionalist argument Premise #1. Functionalism about mental states is true. Premise #2. Some externally realized states play the distinctive causal role of what we already recognize to be mental states. Therefore, some externally realized states are mental states (and thus the mind is extended, so long as we assume the mind is where the realizers of its states are). In support of Premise #2, consider Otto and his notebook

Computational-processing version Premise #1. The essence of a given type of cognitive operation (such as manipulating an image) is its distinctive causal profile. Premise #2. Some (at least partly) external processes have the same cognitive profiles as those we already recognize to be cognitive processes. Therefore, some cognitive processes are at least partly external (so cognitive processing extends beyond the boundary of the skin). In support of Premise #2, consider Tetris (Kirsh and Maglio and C&C’s hypothetical case)

The Causal-Explanatory Kinds Argument --Grouping the internal and (at least partly) external states (and processes) together yields more scientifically useful kinds. --Thus, according to our best cognitive science, mental and cognitive kinds are realized at least partly by the external environment. --Thus, the mind (or cognitive system or cognitive processes) are extended.