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Siena, LS09 - Intenzionalità1 La naturalizzazione dell’intenzionalità Sandro Nannini (Università di Siena)

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Presentation on theme: "Siena, LS09 - Intenzionalità1 La naturalizzazione dell’intenzionalità Sandro Nannini (Università di Siena)"— Presentation transcript:

1 Siena, LS09 - Intenzionalità1 La naturalizzazione dell’intenzionalità Sandro Nannini (Università di Siena)

2 Siena, LS09 - Intenzionalità2 Il problema mente-corpo nella vita quotidiana EE  ……P(+M)  (D)  A SD  SP ..C…  N  R (Suonano, vado ad aprire!) (Suonano, vado ad aprire!)

3 Siena, LS09 - Intenzionalità3 Il dualismo interazionistico P  …D   SD  SP ..CP   CD ..N  R Difficoltà: la chiusura del mondo fisico

4 Siena, LS09 - Intenzionalità4 Il naturalismo SD  SP ..CP ..CD ..N  R Teoria dell’identità FunzionalismoEliminativismo Riduzionismo ontologico / Riduzionismo metodologico

5 Siena, LS09 - Intenzionalità5 Naturalising mental states A mental State X is naturalised iff:A mental State X is naturalised iff: 1.We know how X is implemented by a functional state Y that has the same causes and brings about the same effects than X (functional reduction). 2.We know how the functional state Y is implemented by a brain process Z (neurological implementation). “X” belongs to the language of folk psychology, “Y” to the language of cognitive psychology, “Z” to the language of neurosciences.

6 Siena, LS09 - Intenzionalità6 Naturalising mental states Functional reduction [1] is a task of cognitive psychologists, neurological implementation [2] is a task of neuroscientists. Functional reduction [1] is a task of cognitive psychologists, neurological implementation [2] is a task of neuroscientists. The step (2) presupposes the step (1) and vice versa (top down explanation and bottom up explanation).The step (2) presupposes the step (1) and vice versa (top down explanation and bottom up explanation). Both steps presuppose a previous conceptual analysis and modification of the language of folk psychology (this is the task of philosophers).Both steps presuppose a previous conceptual analysis and modification of the language of folk psychology (this is the task of philosophers).

7 Siena, LS09 - Intenzionalità7 Weak Naturalism and Strong Naturalism W.N. : The truth of (1) is sufficient to naturalise X and such a naturalisation is in principle always possible.W.N. : The truth of (1) is sufficient to naturalise X and such a naturalisation is in principle always possible. S.N. : Also the truth of (2) is necessary to naturalise X. If no Y seems to completely implement X and be completely implemented by Z then either Y was not found out yet or there is a residue of X that cannot be naturalised. Such a residue does not belong to the reality. It is a “fiction” of our mind that has no causal efficacy.S.N. : Also the truth of (2) is necessary to naturalise X. If no Y seems to completely implement X and be completely implemented by Z then either Y was not found out yet or there is a residue of X that cannot be naturalised. Such a residue does not belong to the reality. It is a “fiction” of our mind that has no causal efficacy.

8 Siena, LS09 - Intenzionalità8 Perception and sensory-motor coordination Animals acquired the ability to perceive some features of the external world and of their own body in order to execute movements apt to increase the probability to survive (e.g. by catching preys or avoiding plunderers).Animals acquired the ability to perceive some features of the external world and of their own body in order to execute movements apt to increase the probability to survive (e.g. by catching preys or avoiding plunderers).

9 Siena, LS09 - Intenzionalità9 Perception and sensory-motor coordination Human senses and human sensori-motor coordination are the result of biological evolution.Human senses and human sensori-motor coordination are the result of biological evolution. Biologicalevolution

10 Siena, LS09 - Intenzionalità10 Perception and sensory-motor coordination: Representation-Action Theory (RAT) Perceptions can be conscious or unconscious: in both cases they are mental representations of the internal and external world.Perceptions can be conscious or unconscious: in both cases they are mental representations of the internal and external world. Human beings construct a representation of the external world in order to move and act in it.Human beings construct a representation of the external world in order to move and act in it.

11 Siena, LS09 - Intenzionalità11 The computational brain According to the RAT the brain acquires by means of the senses a certain amount of information about some regularities of the external world as regards the distribution of matter and physical events in space and time and changes the format of such information step by step until a pattern of motor neurons activity able to trigger a right motor response is produced.According to the RAT the brain acquires by means of the senses a certain amount of information about some regularities of the external world as regards the distribution of matter and physical events in space and time and changes the format of such information step by step until a pattern of motor neurons activity able to trigger a right motor response is produced.

12 Styles of brain computation No!!! No representations May be! A Brooks’ robot Unlikely! Symbolic representations Subsymbolic representations

13 Siena, LS09 - Intenzionalità13

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15 Siena, LS09 - Intenzionalità15 Naturalising perceptions according to the RAT Functional reduction A perception is functionally reducible to an intermediate step in the information processing of sensori-motor coordinationA perception is functionally reducible to an intermediate step in the information processing of sensori-motor coordination Therefore it is similar to the activity pattern of hidden units in an artificial neural network and is describable as a vector in a state space.Therefore it is similar to the activity pattern of hidden units in an artificial neural network and is describable as a vector in a state space.

16 Siena, LS09 - Intenzionalità16 Naturalising perceptions according to the RAT Neural implementation Perceptions as vectors in a space state are biologically implemented by the dynamics of brain processes.Perceptions as vectors in a space state are biologically implemented by the dynamics of brain processes.

17 Siena, LS09 - Intenzionalità17 Criticisms on the RAT 1. The sensory motor coordination does not need any inner representation of the external world (Antirepresentationalism; e.g. Brooks’ robots). 2.Perceptions are conscious. Brain processes cannot be conscious (Mind-Body Problem: can consciousness be naturalised?). 3.Perceptions are ‘intentional’ states. No brain process can be ‘intentional’ (semantic relations are not reducible to causal relations): a)The possibility of deceptive perceptions b)The neural implementation of contents c)The identification of a real object by means of a phenomenal object.

18 Siena, LS09 - Intenzionalità18 Criticisms on the RAT 1. The sensory motor coordination does not need any inner representation of the external world (Antirepresentationalism; e.g. Brooks’ robots).

19 Siena, LS09 - Intenzionalità19 A reply to (1) Mice in a labyrinth

20 Siena, LS09 - Intenzionalità20 A reply to (1) M1s recognise red (R), green (G) and yellow (Y) colours and follow these rules: 1)‘If R go to right’ 2)‘If G go to left’, 3) ‘If Y go ahead’ Therefore they are able to reach the food if they enter the labyrinth from South. If they enter from West they have no chance to reach the food.

21 Siena, LS09 - Intenzionalità21 A reply to (1) M2s instead enter the labyrinth sometimes from South and sometimes from West. They can reach the food in both cases because they are able to remember from which entrance they came and to learn by trial and error that if they enter from South they must follow the rule (1) but if they enter from West they must follow the rule (1*), that is, ‘If R go ahead’.

22 Siena, LS09 - Intenzionalità22 A reply to (1) M3s are able to construct by trials and errors a map of the labyrinth. They remember that after entering the labyrinth from South they went to East as they turned to left at the red square. Moreover they somehow have learned (or have the inborn knowledge) that East and West are opposite directions. Therefore, even if they never used the entrance West they are able to forecast that if they entered the labyrinth from West they should go ahead at the red square instead of going to right as they always did till that moment in their life.

23 Siena, LS09 - Intenzionalità23 A reply to (1) In other words, the richer and more ‘objective’ the representation of the labyrinth is the more flexible and efficient the behaviour of the mouse is. Similarly human beings cannot work like Brooks’ robots. They need an inner representation of the environment in which they act. Otherwise their behaviour would not be so flexible as it is. Mental representations are in humans ‘multi-purpose’ representations.

24 Siena, LS09 - Intenzionalità24 Criticisms on the RAT 2.Perceptions are conscious. Brain processes cannot be conscious (Mind-Body Problem: can consciousness be naturalised?).

25 Siena, LS09 - Intenzionalità25 A reply to (2) There is a double disjunction between perception and consciousness: BlindsightBlindsight Anton’s syndromeAnton’s syndrome

26 Siena, LS09 - Intenzionalità26 Blindsight Blindsight allows people to use visual information they get through their eyes even though they have no consciousness of the visual experience. Perception without consciousness

27 Siena, LS09 - Intenzionalità27 The doctor asks what is on the table in front of you: “A clock” you say as though the doctor is an idiot. Anton’s syndrome Consciousness without perception

28 Siena, LS09 - Intenzionalità28 A reply to (2) Conclusion: you can perceive something without been aware of perceiving it and you can be aware of perceiving something without really perceiving it.Conclusion: you can perceive something without been aware of perceiving it and you can be aware of perceiving something without really perceiving it. Consciousness and perception are two distinct phenomana implemented by different brain processes.Consciousness and perception are two distinct phenomana implemented by different brain processes. The RAT naturalises only ‘mere perceptions’, that is, the functional basis common to all perceptions independently of their being conscious or unconscious.The RAT naturalises only ‘mere perceptions’, that is, the functional basis common to all perceptions independently of their being conscious or unconscious.

29 Siena, LS09 - Intenzionalità29 Criticisms on the RAT 3.Perceptions are ‘intentional’ states. No brain process can be ‘intentional’ (semantic relations are not reducible to causal relations): a)The possibility of deceptive perceptions

30 Siena, LS09 - Intenzionalità30 S O* R F. Dretske’s theory: R(O*)O  B R(O*) is true iff O  B is true. A girl sees a cat and her perception is true because it is caused by an animal that is really a cat. B O A reply to (3a) B

31 Siena, LS09 - Intenzionalità31 S O* R The girl is looking at a squirrel but in the dark she sees a cat: O’  R(O*) R(O*) O’  R(O*) is true but R(O*) is false. B B O‘ An objection on Dretske‘s theory

32 Siena, LS09 - Intenzionalità32 The RAT reply to (3a) D(G*) R(O*) D(G*) & R(O*): The girls pursues the goal G to carry the cat in her arms (D(G*)) and executes an action A in order to get G. Perceiving the cat (R(O*)) is necessary to get G because A is caused by D(G*) & R(O*): O  R(O*) [& D(G*)]  A  G

33 Siena, LS09 - Intenzionalità33 A reply to (3a) D(G*) R(O*) B G O A T1 T2

34 Siena, LS09 - Intenzionalità34 R(O*) Dretske’s theory O A reply to (3a) B Mind Body S Physical world The RAT Physical world O Mind R(O*)D(G*) R(S*)R(W*) R(W* S*) S G Body B Hand etc. Emotions

35 Siena, LS09 - Intenzionalità35 A reply to (3a) (a) is a valid objection against Dretske’s theory but not against the RAT.

36 Siena, LS09 - Intenzionalità36 Criticisms on the RAT 3.Perceptions are ‘intentional’ states. No brain process can be ‘intentional’ (semantic relations are not reducible to causal relations): b)Semantic relations are necessary conceptual relations. Causal relations are contingent empirical relations: how can a chain of causal relations implement a semantic relation?

37 Siena, LS09 - Intenzionalità37 A reply to (3b) Contents can be naturalised by means of the ‘adverbial theory’ (of perceptions etc.). “I see red” means “I see redly”: the content of a mental representation is part of its form. Therefore it can be implemented by certain physical properties of a brain process.

38 Siena, LS09 - Intenzionalità38 An objection to the adverbial theory 1 1 I see a green square I see a red circle 2 2 I see a red square I see a green circle I see greenly, squarely, redly, and circulary Distinguishing between (1) and (2) is impossible.

39 Siena, LS09 - Intenzionalità39 A reply to 3b (In defence of adverbial theory) Many neuroscientists think that the form and the colour of a same object are connected by the brain thanks to a common temporal code (synchronisation). Many neuroscientists think that the form and the colour of a same object are connected by the brain thanks to a common temporal code (synchronisation). Therefore the difference between perceiving (1) and perceiving (2) might be implemented by the difference between two dynamics of the brain. Therefore the difference between perceiving (1) and perceiving (2) might be implemented by the difference between two dynamics of the brain.

40 Siena, LS09 - Intenzionalità40 Criticisms on the RAT 3.Perceptions are ‘intentional’ states. No brain process can be ‘intentional’ (semantic relations are not reducible to causal relations): c)A functional state of the brain cannot identify the real object from which is caused and on which the action of the agent is directed. Therefore the RAT is insufficient to explain why perceptions are instead sufficient to identify external objects.

41 Siena, LS09 - Intenzionalità41 A reply to 3c: the 1-eaters and the 2- eaters 1000200000 0100000002 0010000000 0001222200 0000100000 0020010000 0000001222 ?????????? ?????????? ?????????? 100020000001000000020010000000000122220000001000000020 0100000000001222?????????????????????????????? 100020000001000 000020010000000 000122220000001 000000020010000 0000001222????? ??????????????? ?????????? Which is the right representation? It depends on what you eat!

42 Siena, LS09 - Intenzionalità42 A reply to (3c): frogs and flies A frog recognizes flies as food only if they are moving.A frog recognizes flies as food only if they are moving. We human beings instead recognize flies as flies independently of their movements.We human beings instead recognize flies as flies independently of their movements. Therefore, the representation that an animal has of its environment is functional to the actions that it is able to execute in that environment. Therefore, the representation that an animal has of its environment is functional to the actions that it is able to execute in that environment.

43 Siena, LS09 - Intenzionalità43 A reply to (3c): frogs and flies It is not the case that we human beings see flies as they are, frogs instead see them as they appear to them.It is not the case that we human beings see flies as they are, frogs instead see them as they appear to them.

44 Siena, LS09 - Intenzionalità44 A reply to (3c) Mental representations are constructions of the mind (=brain), not the copies of real objects.Mental representations are constructions of the mind (=brain), not the copies of real objects. There is similarity between the activity patterns of hidden units in an artificial neural network and mental representations: they are a representation (= a state space partition) of the input apt to get the desired output.There is similarity between the activity patterns of hidden units in an artificial neural network and mental representations: they are a representation (= a state space partition) of the input apt to get the desired output. Every species lives in its own phenomenal world adapted to a certain kind of interaction with the real physical world.Every species lives in its own phenomenal world adapted to a certain kind of interaction with the real physical world.

45 Siena, LS09 - Intenzionalità45Conclusion Perceptions can be naturalised only if the common sense concept of ‘perception’ is radically changed: perceptions are not copies of real objects passively received from the external world but formats given to sensory inputs in order to construct a stable and multi-purpose model of reality that is able to control the very flexible behaviour of human beings.Perceptions can be naturalised only if the common sense concept of ‘perception’ is radically changed: perceptions are not copies of real objects passively received from the external world but formats given to sensory inputs in order to construct a stable and multi-purpose model of reality that is able to control the very flexible behaviour of human beings. These perceptions can be functionally reduced and therefore can be implemented by brain processes.These perceptions can be functionally reduced and therefore can be implemented by brain processes.

46 Siena, LS09 - Intenzionalità46 Action theory and cognitive turn by Sandro Nannini (University of Siena)

47 Siena, LS09 - Intenzionalità47 Linguistic turn and cognitive turn From the meaning of psychological terms to empirical hypotheses on the nature of mental states (from G. Ryle to naturalism in the philosophy of mind).From the meaning of psychological terms to empirical hypotheses on the nature of mental states (from G. Ryle to naturalism in the philosophy of mind). My aim is to defend the causal theory of action from a naturalistic point of view by doing a “cognitive turn” in action theory as well.My aim is to defend the causal theory of action from a naturalistic point of view by doing a “cognitive turn” in action theory as well.

48 Siena, LS09 - Intenzionalità48 “Intentionalists” and “causalists” Intentional explanations “She raised her arm because she intended to greet a friend”.“She raised her arm because she intended to greet a friend”. “She did X because she intended to get Y”.“She did X because she intended to get Y”. “A did X because A intended to get Y and believed that doing X had brought about her getting Y”.“A did X because A intended to get Y and believed that doing X had brought about her getting Y”. I A (Y)  B A (X  Y)  XI A (Y)  B A (X  Y)  X

49 Siena, LS09 - Intenzionalità49 “Intentionalists” and “causalists” Intentional descriptions “She raised her arm because she intended to raise it”“She raised her arm because she intended to raise it” “She did X because she intended to do X”.“She did X because she intended to do X”. “Her doing X was intentional”.“Her doing X was intentional”. I A (X)  XI A (X)  X Every intentional explanation implies an intentional description; “I A (Y)  B A (X  Y)  X” can be so expanded:Every intentional explanation implies an intentional description; “I A (Y)  B A (X  Y)  X” can be so expanded: 1) I A (Y)  B A (X  Y)  I A (X)1) I A (Y)  B A (X  Y)  I A (X) 2) I A (X)  X2) I A (X)  X

50 Siena, LS09 - Intenzionalità50 “Intentionalists” and “causalists” “The logical connection argument” L. Wittgenstein, G. Anscombe, A. Melden, and G.H. von Wright: the causal theory of action is false because it is logically impossible that an intention is the cause of an action.L. Wittgenstein, G. Anscombe, A. Melden, and G.H. von Wright: the causal theory of action is false because it is logically impossible that an intention is the cause of an action. 1) The direct “Logical connection argument”: In “I A (X)  X” the relation “  ” cannot be causal because I A (X) mentions X.1) The direct “Logical connection argument”: In “I A (X)  X” the relation “  ” cannot be causal because I A (X) mentions X. 2) The “verification argument” (von Wright): the presence of I A (X) can be verified only by means of the presence of X.2) The “verification argument” (von Wright): the presence of I A (X) can be verified only by means of the presence of X.

51 Siena, LS09 - Intenzionalità51 “Intentionalists” and “causalists” “The logical connection argument” 1) The direct “Logical connection argument”: In “I A (X)  X” “  ” cannot be causal because “I A (X)” mentions “X” – Reply: in an intentional explanation X is explained by I A (Y) and not by I A (X). 2) The “verification argument” (von Wright): the presence of “I A (X)” can be verified only by means of the presence of X. – Reply: verification  explanation. The example drawn by C.G. Hempel.2) The “verification argument” (von Wright): the presence of “I A (X)” can be verified only by means of the presence of X. – Reply: verification  explanation. The example drawn by C.G. Hempel. The Logical Connection Argument (LCA) does not prove that intentional explanations are not causal explanations.The Logical Connection Argument (LCA) does not prove that intentional explanations are not causal explanations.

52 Siena, LS09 - Intenzionalità52 “The killer nephew” However, intentionalists have still an argument against the causal character of intentional description. “The killer nephew” (KN) proves that intentional descriptions cannot be based on causal relations because there are cases where “I A (X)  X” is true but “I A (X)  X” is false. Usual reply: the wayward causal chains.

53 Siena, LS09 - Intenzionalità53 “The killer alpinist” Counter-reply: “the killer alpinist”. However, either the state of excitement caused the release of the rope at least an instant before than planned or the death of the hated friend was caused both intentionally and unintentionally (that is, the ‘killer alpinist’ is a strange case of co-determination by the same cause but considered under two distinct descriptions since the same mental state is implicitly described both as the intention of killing the friend and as a mere state of excitement).

54 Siena, LS09 - Intenzionalità54 Intentional content and causal explanations But the ‘killer nephew’ and ‘the killer alpinist’ in spite of these limits throw light on a weaken point of the causal theory of action that a causalist cannot evade: Intentions do not explain actions (or describe them as intentional) simply because they are the causes of the corresponding actions but also because of their content. In order to intentionally describe the intentional action of doing X it is not sufficient to show that the action was executed because of the intention of doing X. It is also necessary to show that the intention was not causally efficacious merely thanks to its being a state of excitement whatsoever but thanks to its content, that is, to its being the intention of doing X.

55 Siena, LS09 - Intenzionalità55 Intentionality naturalised Conceptual analysis Intentional and non-intentional descriptions 1) S caused the death of the friend1) S caused the death of the friend 2) S was P (an intention) and P’ (a state of excitement)2) S was P (an intention) and P’ (a state of excitement) 3) S would have caused the death of the friend even if it was not P’ provided it was P.3) S would have caused the death of the friend even if it was not P’ provided it was P. If instead the first alpinist committed only an involuntary manslaughter then (1) and (2) are still true but (3) is substituted byIf instead the first alpinist committed only an involuntary manslaughter then (1) and (2) are still true but (3) is substituted by 3*) S would have caused the death of the friend even if it was not P provided it was P’.3*) S would have caused the death of the friend even if it was not P provided it was P’.

56 Siena, LS09 - Intenzionalità56 Intentionality naturalised Conceptual analysis The “adverbial theory of intentionality” (ATI) How can intentionality be a monadic property P? This is possible if, for example, “I see a red spot” is equivalent to “I see red-spotly”, that is, if the content of a mental state is interpreted as extensionally identical to the form of the physical process that implements it. However, unless one accepts the mind-body dualism this is not plausible within the limits of the observable open behavior. The examples of the KN or KA cannot be rejected only by means of the conceptual analysis of common language. Causalists need a “cognitive turn” to justify ATI!

57 Siena, LS09 - Intenzionalità57 Intentionality naturalised cognitive sciences (1) The argument of the wayward causal chains becomes obvious and clear if we take into account not only the open behavior but also the part of the causal chain that is internal to the brain. For example, voluntary movements are prepared in the prefrontal cortex, emotions (excitement etc.) are implemented in the lymbic system instead. Moreover if mental representations and desires drive voluntary movements then the content of mental states might be implemented by the dynamics of the brain processes that process information from sensory inputs to motor responses. Artificial networks offer a model for the dynamics of such processes.

58 Siena, LS09 - Intenzionalità58 Intentionality naturalised cognitive sciences (2) Mental states are implemented by brain processesMental states are implemented by brain processes Intentional actions and unintentional actions are caused by different brain processesIntentional actions and unintentional actions are caused by different brain processes The content of our mental states, given a certain train of sensory stimuli, has been established by biological evolution in a way functional to the requirements of the sensori-motor co-ordination in order to surviveThe content of our mental states, given a certain train of sensory stimuli, has been established by biological evolution in a way functional to the requirements of the sensori-motor co-ordination in order to survive The content of mental states is implemented by the dynamics of the neural processes that implement such statesThe content of mental states is implemented by the dynamics of the neural processes that implement such states This dynamics controls the motor response necessary to improve the probability of survivingThis dynamics controls the motor response necessary to improve the probability of surviving Therefore the Intentionality of mental states is naturalizable and plays an essential role in the causal chain that connects our brain processes to our bodily movements (i.e., in a naturalistic perspective, the causal chain that connects our mental states to our actions, including our intentional actions).Therefore the Intentionality of mental states is naturalizable and plays an essential role in the causal chain that connects our brain processes to our bodily movements (i.e., in a naturalistic perspective, the causal chain that connects our mental states to our actions, including our intentional actions).

59 Siena, LS09 - Intenzionalità59 The causal theory of action rescued Therefore the recent philosophy of mind oriented towards naturalism has completely rescued the good old-fashioned causal theory of action from the attacks of which it was the object during the fifties and the sixties by Neowittgensteinians.Therefore the recent philosophy of mind oriented towards naturalism has completely rescued the good old-fashioned causal theory of action from the attacks of which it was the object during the fifties and the sixties by Neowittgensteinians.

60 Siena, LS09 - Intenzionalità60 Tahnk you for your attention!

61 Siena, LS09 - Intenzionalità61 Thank you for your attention! Thank you for your attention!


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