Philosophy of mind between reduction, elimination ...

480

Fabio Baccruni

as recognized donnitivity? In this perspective, mental causality could be seen as a special kind of placebo effect involving the mind making itself causally efficacious.

BIBLIOGRAPHY III [2]

[3] [4] [5]

[6] [7]

K. Bennett. Why the exclusion problem seems intractable and how just maybe to tract it. Nous, 37 (3): 471-497,2003. " , N. Bl00-. Can the mi~d change the world? In G. BoolO$ (ed.), Meaning and Method: Essays 1.7~ Honor of Hilary Putnam, Cambridge University Press, Cambridge MA, 1990; now also m C. Macdonald and G. Macdonald (eds.), Philosophy of Psychology Blackwell Oxford 1995. ' , N. Block. Do causal powers drain away? Philosophy and Phenomenological Research, 67 (1), 133-150,2003. Th. M. Crisp and T. ~. Warfield. Kim's master argument. NoUs, 35: 304-316, 2002. D. l?ennett. True believers. In ~.F. Heath (ed.), Scientific Explanation, Oxford University Press, Oxford 1981; now In W. G. Lycan (Cd.), Mind and Cognition, Blackwell Oxford, 2nd ed. 1999. ' A.I. Goldman. The compatibility of mechanism and purpose. The Philosophical Review 78 (4)' 46&-482, 1969. ' J. Kim. Concepts of.supervenience. Philosophy and Phenomenological Research, 45: 153176, 1984; now also m Supervenience and Mind. Cambridge University Press Cambridge ~1~

,

,

[8J J. K!m. Mind.in a Physical World, MIT Press, Cambridge, MA 1998. [9] .J. I~m1. Blockmg causal drainage and other maintenance chores with mental causation. Ph~lo80phy and Phenomenological Research, 67 (1): 151-176,2003. [10J E.J. Lowe. Causal closure principles and emergentism. Philosophy W~ . , 75 (4)'. 571-585 , [11] E. Marcus. Mental causation in a physical world. Phylosopmcal Studies 122' 27-50, ' . 2005. [12] S. Yablo. Mental causation. The Philosophical Review, 101: 245--280, 1992.

Philosophy of mind between reduction, elimination and enrichment WOLFGANG HUEMER

1

Introduction

Philosophers of mind and neuroscientists a,rguably describe the same range of phenomena: they formulate theories of how human beings gather information about relevant aspects of their environment, how they form beliefs and desires, and what kind of processes are going on within them that allow them to act on the world. They do so, however, in very different ways: while neuroscientists focus on the causal processes that take place in our nervous system at a stlbpersonal level, philosophers focus on menta,l episodes: they describe human beings as persons who have propositional attitudes that stand in rational relations (of justifying and being justified) to one another. These differences in approaches can be explained by the diverging interests of philosophers and neuroscientists, respectivelY"which can be best illustrated with Wilfrid Sellars' distinction between the manifest and the scientific image of man. The manifest image, according to Sellars, is a "sophistication and refinement of the image in terms of which man first came to be aware of himself as man-in-the-world" [9, p. 18]. Human beings came to be aware of themselves as having mental episodes, which they experience from a firstperson point of view. In the attempt to explain this phenomenon, they soon started to develop a theory that was step by step refined over the centuries - a theory that is (nowadays) often referred to as "folk psychology". This theory describes (a considerable part of) mental episodes as propositiona,l attitudes that justify or are justified by other mental episodes. In short, the manifest image leads to a theory that describes human -beings in a conceptual framework of persons who understand themselves as occupyirig a certain position in this world and who have perceptions of, hold beliefs about, and act on objects in their environment, and who can imagine scenarios they have so

far not (yet) encountered. The scientific image, on the other hand, is characterized by the development of scientific theories that postulate "imperceptible objects and events for the purpose of explaining correlations among perceptibles" [9, p. 19]."When we formulate a theory of the mind within this scientific image, we describe causal processes that take place in our nervous system; 'processes, that is, that are not perceptible (at least not directly, Le. without the means of sophisticated medical imaging techniques) and that provide a basis for explaining the observable behaviour of human beings at a sub-personal level. A good part of work in the philosophy of mind, especially in the twentieth

482

Wolfgang Huemer

century, focused on the question of how these tvvo levels of description are related. Scientific theories are often considered to be more e..'Xact than the ones formulated within the manifest image for they are based on empirical data and experiments and are formulated in the language of mathematics. This raises the question of whether philosophers should aim to incorporate the results of the scientific image into their theories. Should the manifest image be reduced to or replaced by the scientific image? Can the two images coexist and complement each other, thus providing a more comprehensive understanding of the mind? Or do we rather have to accept the fact that the two frameworks provide two descriptions of different aspects of the phenomena in question; two descriptions that are so different that we cannot merge them into one unified account? In this paper I will argue that there are specifically philosophical desiderata that a theory of mind should satisfy; desiderata that scientific theories cannot account for - at least not in their actual shape. The question, I will suggest, is not how to reduce philosophical theories of the mind to the neurosciences, nor how to eliminate them from our scientific vocabulary, but rather whether and how scientific theories can be enriched to account for those aspects that are relevant in the philosophical debate. In the first section of this paper I will spell out the philosophical desiderata for a theory of the mind. I will then discuss two philosophical approaches that emphasize the importance of the results of scientific theories for a philosophical understanding of the mind, reductionism and eliminativism, with the aim to show that a scientifically oriented approach to the philosophy of mind should bet on eliminativism rather than on reductionism. In the concluding section I will argue, however, that radical eliminativist strategies must fail for they cannot account for the very fact that we formulate theories that satisfy the standards of rationality. I will then discuss the question of whether, at the current state of research, we should focus our efforts on the question of how the scientific and the manifest image are related and whether or how they can - at some point in the future - be merged into a synoptic vision that provides a more comprehensive theory of the mind.

2

Philosophical desiderata for a theory of the mind

Philosophers conceive of human beings as rational agents who interact with their (social and physical) environment: they collect information which they receive, at least in good part, through their sense organs, and perform actions on objects around them. By forming beliefs about their environment as well as about themselves and generalizing from empirical observations they come to represent the world in a (more or less) coherent way. Moreover, they are able to communicate their picture of the world to other persons and so confront it with their ways of seeing the world, a process which can result in their revising, adapting, enriching, or sophisticating their own views. In order to explain these facts, philosophers typically describe persons as having a large number of propositional attitudes that stand in rational relations to one another. Rationality, however, contains an intrinsically normative element, which manifests itself in the possibility of error and corrections: we

Philosophy of mind between reduction, elimination and enrichment

483

can misperceive the world around us, make illegitimate inferences, and hold wrong beliefs. Moreover, propositional attitudes have a content that' can be expressed linguistically and can so be communicated to other persons. In case of disagreement l other members of our linguistic community can criticize our beliefs. They can point out our errors or inconsistencies in Qur system of beliefs and justify this critique with arguments, which we are free to accept or not to accept - after all l we are free to insist in our false beliefs. Scientific theories - at least the ones we know today - on the other hand, are characterized by the fact that they abstract from all normative concerns: science is (supposed to be) value-free. Scientists are interested in the causal workings of the machinery, as it were; they describe causal relations that take place in our nervous system, but they do not have the means to state that these causal relations take place wrongly or that they ought to be corrected. Thus, the attempt to explain the normative aspect of the mental in terms of the causal relations studied by the sciences constitutes, as Wilfrid Sellars has pointed out, "a radical mistake - a mistake of a piece with the so-called 'naturalistic fallacy' in ethics" [10, p. 19, §5J. This does, of course, not show that the results of neurophysiological research is irrelevant to the philosophical understanding of the mind; after all, our cognitive processes take place in the brain and a better understanding of our cerebral processes can illuminate our understanding of the enabling conditions for our having mental phenomena. Moreover, the fact that we can describe mental episodes in two very different ways does not entail a form of ontological dualism. I do want to emphasize, however, that philosophers and neuroscientists study very different aspects of the mind. Knowing that a certain stimulation of the retina can cause a certain cerebral process does not explain why a certain perceptual experience justifies a certain belief. This suggests that a scientific approach ca!1llot be suffi.cie~or formulating a comprehensive theory of the mindj it will (in the best case) need to be complemented by a theory that can account for the normative and the social aspects of the mental. Philosophers who argue that neuroscientific theories are complete will have to argue that a more elaborate and sophisticated neurological theory of the mind, one that will be formulated in the future, will be able to account for these features, or else provide an argument that shows that they can be neglected and thus eliminated from our scientific study of the mind.

3

Reductionism versus eliminativism

The philosophy of mind of the twentieth century was strongly characterized by the debate of whether and how philosophical theories of the mind can be substituted by or at least reconciled with scientific theories. The urge to do so was arguably the result of the widespread scientism at the beginning of the century as well as of a post-Vienna Circle conception of the unity of the sciences that was shared by most analytic philosophers until very recentlyl, 1 A conception, that is, that was often attributed to the Vienna Circle, but was in fact elaborated by Paul Oppenheim and Hilary Putnam in [7J as well as Ernest Nagel in [5] and many others. The canonical conception of the unity of the sciences of the Vienna Circle

484

Wolfgang Hu€m€r

according to which all special sciences, including biology, psychology, sociology, and economics, etc., could be reduced to more basic sciences or else should be eliminated from our scientific discourse. In the early twentieth century, most (analytic) philosophers of mind suggested that psychological descriptions of mental episodes ~ including propositional attitudes, the existence of which was not questioned - can in principle be reduced to scientific descriptions of events that take place in our nervous systems. The first theories, the (nowadays) so-called type-type identity theories, argued that specific types of mental episodes (e.g., pain, or beliefs like the belief that the earth moves around the sun) were identical with specific types of neurological processes (the firing of C-fibers or a specific activation pattern in the brain, respectively), This gave raise to the hope that a philosophical or psychological theory of the mind could in principle be reduced to neurology. The proponents of this view were ready to admit that we would have to wait for further progress of the neurosciences to perform this inter-theoretical reduction, but suggested that, once the reduction is completed, we will be able to account for all philosophical desiderata for a theory of the mind in terms of neurology. It is worth noting, however, that according to this conception the fact that a theory can be reduced to another, more basic theory does not show that the reduced theory is obsolete or false. It rather shows that there are systematic relations between the reduced theory and the theory to which it is reduced - and that the latter has (at least) the same explanatory power as the former. This conception of intertheoretical reduction does allow for the possibility, however, that some aspects of the reduced theory might be slightly transformed - and thus rendered more precise - in this process; just as the notion of temperature was slightly altered when it was reduced to that of kinetic energy of molecules. In consequence, reductionism in the philosophy of mind does not entail that it is wrong to attribute propositional attitudes to human beings, nor that folk psychology is a theory that should be substituted by a more basic theory. Reductionists, thus, can admit that our having propositional attitudes that stand in rational relations to one another is a crucial fact that needs to be explained by a theory of the mind - but they do not spell out how a neurological theory could address these aspects; they merely express their hope that future progress of neurology will make this reduction possible. Various proponents of this view do suggest, however, tha,t there are systematic relations between folk psychology and neurology and that a better understanding of these relations will also lead us to reformulate - and thus develop a more precise version of - folk psychology. These early identity theories were soon criticized by functionalists and anomalous monists (among others), who pointed out that they were too narrow, ascribing, as they do, mental episodes only to organisms that have a did not insist in the reduction of theories, but put its emphasis on the unity of language that allows for an encyclopedia, a patchwork that combines results of various scientific disciplines; Otto Neurath, for example, explicitly discarded the importance of a reduction of theories in [6, p. 362]. In the last two decades of the last century,' an increasing number of analytic philosophers began to take a critical stance towards the idea that the unity of the sciences is to be achieved by means of intertheoretic reduction.


485

nervous system (more or less) equivalent to ours. If type-type identity theory was rightl we could not hold that, for example, intelligent extraterrestrial life fonus or non-human animals like octopuses, whose nervous system is substantially different from ours, could experience pain or hold the belief that the earth moves around the sun. 2 It was argued that mental episodes could be realized in various different ways and that they, are nothing but functional states of the brain (or some other system). While these theories avoid the pitfalls of ontological dualism, they also raise a serious challenge to the hope that a neurological theory will be able to address the philosophical desiderata for a theory of the mind. A more radical attempt to establish a "neurophilosophyn, i.e., to replace the philosophy of mind with a neuroscientific theory of the nervous system, was proposed by Paul Churchland, who criticizes reductionist theories for making too many concessions to what I have called, using Wilfrid Sellars' terminology, the manifest image. It is, Churchland argues, a mistake to hold on to propositional attitudes and try to reconcile them with a scientific description of the nervous system - as reductionists dOj they should rather be eliminated from our scientific vocabulary and replaced by more adequate and precise descriptions of our actual cerebral processes at a sub-personal level. Churchland argues that in our brain we do not find a linear series of activations of single (groups of) neurons - which could be identified with propositional attitudes or parts thereof - but rather networks of neurons that can be represented by connectionist networks that are composed of units at different levels, where all units at one level are connected with all units at the subsequent level. According to connectionism, these units have a (numerical) activation value; their connections have a certain weight, which, again, is represented numerically. The whole network, thus, consists of a pattern of numerical values that can be represent~d by a matrix. We can feed the system with a (numerical) input, which, when being propagated through the system, is transformed by the units' activation values and the weights of their connections and thus produces a specific (numerical) output. By adjusting the activation values of the units and the weights of their connections, a system can be trained to react to a certain kind of input by producing a certain kind of output. In this way, the system can, as connectionists argue, learn to perform certain tasks. The surprising success of early connectionist systems has soon raised the plausibility of this approach. Churchland describes a connectionist network with 13 units at the input level, seven units at the hidden level, and two units at the output level which, after a learning process, could be trained to decide whether a (numerically encoded) echo sonar reading was reflected by a rock or by a mine. 3 The learning process involves a great number of signals of which it was known by the scientists who performed the training whether they were reflected by rocks or mines. These signals were run through 2 In a classic passage, Hilary Putnam states: "Thus if we can find even one psychological predicate which can clearly be applied to both a mammal and an octopus (say 'hungry'), but whose psycho-chemical 'correlate' is different in the two cases, the brain-state theory [i.e., type-type identity theory] has collapsed" [8, p. 288J. 3 Cf. (2, pp. 262ft].

486


Wolfgang Huemer

the system several thousand times. By continuously adjusting the values of the units clud the weights of their connections (by means of a mathematical formula, the so-called delta-rule), the system could be trained to produce the desired output: after the training process, the system, when confronted with a hitherto unknown echo sonar reading, is (almost always) able to correctly decide whether it was reflected by a rock or a metallic object (Le., a mine). This result is relevant because, as Churchland explains, experienced soldiers are able to hear whether the sonar reading was reflected from a rock or a mine - a,nd that, even though there are no specific characteristica that would allow us to distinguish the two: even the soldiers were not able to explain how they come to their conclusion; they "just hear" the difference. This suggests that the system works in a way similar to (a relevant part of) the human brain. Churchland even goes so far as to say that the system "knows" whether there is a mine or a rock, using quotation marks to highlight that this is not a form of propositional knowledge. It is central to Churchland's argument, however, that the system does not contain symbolically represented information on rocks or mines (or rather: rocks and metallic objects; the system cannot distinguish between sonar readings reflected by mines and those reflected by other metallic objects), nor does it possess the concepts ROCK or METALLIC OBJECT. Moreover, it is impossible to say in which part of the system this "knowledge" is located. All we get is a, matrix of (numerical) activation values and weights of connections. Thus, Churchland concludes, the "paradigm of symbolic representation" can be given up: known propositions are not located in a determinate part of the system, but rather "embodied" in the system as a whole. In consequence, Churchland argues, we can overcome our inclination to hold on to propositional attitudes and rational relations that hold between them and consequently can eliminate folk psychology in favor of the neurosciences. 4 The connectionist system described by Paul Churchland was developed some twenty years ago. I do not, of course, want to suggest that no relevant progress has been made since then, In particular, it was pointed out that in order to understa,nd the workings of the brain it does not suffice to focus on one subsystem in isolation, we rather need "to study many levels of organization, from molecules, to synapses, neurons, micro networks, macro networks and systems" [3, p. 1871, which suggests that a promising neurophysiological account will have to be far more complex than the connectionist system described. I did present this example in some detail for it illustrates very well that a neurophilosophical perspective invites a shift in paradigms that results in an elimination of the idea that propositional attitudes and the rational relations that hold between them are core elements in a description of the mind 4lt might be noteworthy that Churchland applies this picture also to scientific theories, suggesting that we should conceive of theories as connectionist networks that do not consist of a set of propositions that stand in rational relations (of justifying and being justified) to one anot.her - this would mean to fall back into the "paradigm of symbolic representation" - but rather as system that produces a certain output when being fed with a certain input. This makes it impossible, however, to criticize and revise single propositions of a given theory; one could only adopt or give up theories as a whole; a move Churchland explicitly endorses. Cf. [2].

487

- a tendency that is also characteristic for more recent developments in the field of "neurophilosophy" . Like reductionists, eliminativists are happy to acknowledge tha.t at the current state of the art neurological theories are not yet able to substitute philosophical theories of the mind. They are convinced, however, that once we are able to formulate a mature neurological theory we will understand that folk psychology is nothing but an immature and inadequate attempt to describe the human mind that is based on a series of highly questionable presuppositions. Unlike reductionists, however, eliminativists take note of the most recent developments of neurophysiology. They do not hold on to a philosophical picture of the mind nor do they limit themselves to express their hopes that at some point in the future we will be able to reformulate this picture in terms of neurology, but take the idea serious that a neurological theory of the mind - a theory, that is, that takes into account the actual architecture of the nervous system - might propose a different picture; a picture that might substantially revise our conception of the mind. If one admits that the results of neurology are pertinent to our philosophical understanding of the mind, this seems to suggest that eliminativists are in a better position, since they do take into account the most recent results of neurology.

4

On the prospects of a unified account

But why, we might ask, should we expect that a faithful description of the processes that actually take place in our nervous system is able to illuminate our philosophical understanding of the mind? I do not want to deny tha.t they are crucial for our understanding of the workings of our brain, nor do I want to diminish the importance of this project - I do not mean to take a critical stance towards the neurosciences. I do want to raise the question, however, what kind of philosophical illuminations we can 'get from these theories? It seems obvious to me that Churchland's position - but also the strong identity theories - are committing a fallacy that is analogous to the psycho logistic fallacy that was criticized by Frege and HusserI more than one hundred·yea!:s __ ._ ago. A detailed study of our brains can at best show how our brain actually proceeds certain kinds of stimulus. It can show what causa.} processes take place in our nervous system, but cannot say anything about the nature of our mental episodes, their propositional contents and the rational relations that hold between them. rIb do so it would have to be able to address the normative level of the rational relations that hold between our mental episodes: beliefs, for example, can be true or false, they have a truth-value, and justify or are justified by other beliefs - by inferences (in a large sense) which we can, but do not have to draw. Our mental episodes, to come back to 3e11a,rs' terminology, a.re positions in a game of giving and asking for reasons. As ra.tional beings we strive for truth (however you want to define "truth"); a.nd it is part of the very concept of "belief" that we should hold true and revise wrong beliefs and similarly for the concept of inference. Moreover, a person who holds a belief takes responsibilities: the responsibility to justify or revise her beliefs when asked to do so. All these aspects belong to the core of the concept of

488

Wolfgang H uemer

person that plays a crucial role in the manifest image. In addition, eliminativism cannot account for the very fact that we formulate scientific theories like neurology. After all, also theories contain a normative element: also theories strive for truth, aiming, as they do, to describe (a relevant part of) the world correctly. Moreover, a scientific theory has to fulfill certain standards: in order to qualify as a scientific theory it has to obtain data in the ways required by the methodological standards tha.t hold in this discipline and justify its hypotheses by arguments that are sensitive to the rules of rationality. This shows that even to account for the very fact that human beings are able to formulate scientific theories, we need to account for the intrinsically normative aspect of rationality. The neurosciences (at least in their current shape), however, cannot address these normative issues. For methodological reasons they have to limit themselves to describe the causal relations that take place in our nervous system with scientific necessity and to describe the nervous apparatus at a sub-personal level. Thus, they can at best explain how a certain stimulation of the retina causes a certain neuronal activity, but not why a perceptual experience can justify an empirical belief. Similarly, they might be able to explain how we come to hold a certain theory of the mind, but cannot explain why this theory is preferable to another less adequate, less coherent, or less simple theory. Churchland, I should note, explicitly reacts to the argument concerning the intrinsically normative aspect of the mental. The arguments he proposes, however, aim into two opposite directions. On the one hand he seems to downplay the strength of the argument by denying that the normative aspect is essential to the realm of the mental. He argues that the fact that the regUlarities ascribed by the intentional core of FP [Folk Psychology] are predicated on certain logical relations among propositions is not by itself grounds for claiming anything essentially normative about FP. To draw a relevant parallel, the fact that the regularities ascribed by the classical gas law are predicated on arithmeti~ cal relations between numbers does not imply anything essentially normative about the classical gas laws. [1, p. 82]

This argument is based on a confusion of two different levels, though, namely that of the description of relations and that of the relations described. There is no doubt that there are rational relations between various descriptions of scientific facts; scientific theories, as we have seen above, contain a normative element. The relations described by these scientific theories, however, are causal, and not rational. The relations described by folk psychology, on the other hand, are rational. In the case of the latter, the nonnative aspect belongs not only to the theory, but also to the entities described by the theory - not only our theories about beliefs, but also the beliefs described by the theory have a truth-value. Churchland misses this point when he suggests that a "normative dimension enters only because we happen to value most of the patterns ascribed by FP" [1, p. 831. On the other hand, Churchland does seem to acknowledge the pertinence of the argument concerning the intrinsic normativity of the mental, but suggests that scientific theories are, or better: will be, at some point in the future, able


489

to account for this aspect better than folk psychology, which, as he suggests, is not without flaws. He notes, for example, that "the laws of FP ascribe to us only a very minimal and truncated rationality, not an ideal rationality as some have suggested" [1, p. 83}. Churchland's point shows at best, however, that folk psychology describes beings who are not perfectly rational; moreover, it still leaves open the possibility that some time in the future, a matured folk psychology will be in a position to provide an even more adequate description of the mind. Churchland does not take this possibility into account, he rather bets on the future development of scientific theories suggesting, as he does, that these normative issues "will have to be reconstituted at a more revealing level of understanding, the level that a matured neuroscience will provide" [1, p. 84])5 Churchland, thus, suggests that in the future scientists will be able to develop a neurological theory that is able to address these issues. With this, he adopts a line similar to that of his teacher Wilfrid Sellars, who argued that in order to get a comprehensive theory of the mind, or, as he formulates it, a synoptic vision, aspects of the manifest image need to be added to the scientific image of man: Thus the conceptual framework of persons is not something that needs to be reconciled with the scientific image, but rather something to be joined to it. Thus, to complete the scientific image we need to enrich it not with more ways of saying what is the case, but with the language of community and individual intentions [9, p. 40].

But Sellars also admits that he is not able to provide a clear idea of how this task is to be achieved. He concludes his essay with the following statement: We can, of course, as matters now stand, realize this direct incorporation of the scientific image into our way of life only in imagination. But to do so is, if only in imagination, to transcend the dualism of the manifE¥'t and scientific images of manof-the-world [9, p. 40].

So the question remains: how can we enrich the neurosciences to put them into a position to address the normative issues of the mental? For the moment being, I want to suggest, we should not get stuck with this question and accept, for methodological reasons, that we are currently facing a pluralism of descriptions: philosophers and neuroscientists do describe the very same set of phenomena, but they do so in very different ways. Philosophers, it seems to me, will have to go a long way to clear conceptual -issues J:elated. to the philosophy of mind; and also neurologists will have to work hard to formulate more precise theories of the causal workings of our nervous system. Since we do not yet have a clear idea how and at what level of analysis the philosophical description of persons as rational agents and the description of their nervous apparatus at a sub-personal level can be reconciled and, in consequence, which parts of the respective theories will have to be refined or altered, it seems to me that both disciplines will optimize their results if they focus on their own projects. 5For a more detailed discussion of Churchland's arguments concerning the normative aspect of the mental cf. [4, pp. 41H].

490

Wolfgang H uemer

The question will turn out to be pressing, however 1 once we are able to formulate more advanced neurological and more precise philosophical theories of the mind. At this point, I think, we will need to pursue two strategies at the same time: we will need to show how propositional attitudes can emerge from neural networks in the brain an thus give an exact description of enabling

conditions for our having mental episodes. A bottom-up strategy alone will not do, however: to get a synoptic vision, we will also need to show how the normative dimension can influence the sub-personal level. After all, this dimension might be crucial for our training up neuronal networks to perform certain tasks. This normative aspect, however 1 is rooted in our capacity to follow rules~ i.e. to act in conformity or contrary to standards that are essentially social: a person can be said to follow a rule - which~ moreover~ holds within a social community - only if her actions can be corrected by the members of this community. If this observation is correct~ it shows that the neurosciences will be able to formulate a comprehensive theory of the mind only if they succeed in capturing this social dimension~ Le. in understanding the nervous apparatus of an individual in its interaction with that of other individuals. Recent research on mirror neurons hints in this direction~ but scientists will be able to reach this goal only if they give up the methodological individualism that is still inherent in their research programs; rather than studying the nervous apparatus of one person they might have to turn to describe those of a community of persons in their interaction. Even when pursuing this strategy~ however~ we might find ourselves in a position that we are not able to formulate a scientific theory that expla,ins how the normative level emerges from the causal order of the world; we might have to accept it as a brute fact that the level 0'£ norms is always already there. In other words, we might not be able to explain where the nonnative aspect comes from - at least at a phylogenetic level; we will be able to do so on an ontogenetic level - or how a certain set of values can be justified scientifically or whether or why it is preferable over another one and might have to conclude that "it is there - like our life" [11~ §559]. This does not seem to be a major problem~ however: explanations have to come to an end somewhere. By adding the normative and the social aspects to our scientific theory of the mind, we might not be able to solve all problems. In trying to do so we will, however~ gain a more comprehensive understanding of propositional attitudes, consciousness and the mind. In short~ we will get a more profound understanding of a central philosophical problem: what is the nature of the mind; and what does it mean to be a person.

BIBLIOGRAPHY [1] P.M. Churchland. Eliminative materialism and the propositional attitudes. The Journal of Philosophy, 78: 67-90, 198!. [2] P.M. Churchland. On the nature of theories: A neurocomputational perspective. In J. Haugeland (ed.), Mind Design If, MIT Press, Cambridge, MA 1997, pages 251-292. [3] P.S. Churchland. Neurophilosophy: the early years and new directions. Functional Neurology 22: 185-195,2007. [4] W. Huemer. The Constitution of Consciousness. A Study in Ana.lytic Phenomenology. Routledge, New York 2005.


491

[5] E. Nagel. The Structure of Science. Problems in the Logic of Scientific Explanation. Hartcourt, Brace & World, New York 196!. [6] O. Neurath. Empirical sociology. The scientific content of history and political economy. In M. Neurath and R. Cohen (eds), Empirism and Sociology, pages 319-421. Reidel, Dordrecht 1973. [7] P. Oppenheim and H. Putnam. Unity of science as a working hypothesis. In H. Feigl, M. Scriven and G. Maxwell (eds), Minnesota Studies in the Philosophy of Science, Vol. 2, University of Minnesota Press, Minneapolis 1958, pages 3-36. [8J H. Putnam. The nature of mental states. In Ned Block (00.), Readings in Philosophy of Psycholo[flJ, vol. 1, Harvard University Press, Cambridge, MA 1980, pages 223-231. [9J W. Sellars. Philosophy and the scientific image of man. In Science, Perception and Reality, Ridgeview, Atascadero 1963, pages 1-40. [10] W. Sellars. Empiricism and the Philosophy of Mind. Harvard University Press, Cam~ bridge, MA 1997. [11] L. Wittgenstein. (OC): On Certainty. G.E.M. Anscombe and G.H. von Wright (eds), trans. by Denis Paul and G.E.M ..Anscombe. Blackwell, Oxford 1969.

New Essays in Logic and Philosophy of Science Edited by

Marcello D'Agostino, Giulio Giorello, Federico Laudisa, Telmo Pievani, and

Corrado Sinigaglia

Volume 1 New Essays in Logic and Philosophy of Science Marcello D'Agostino, Giulio Giorello, Federico Ladisa, Telmo Pievani and Corrado Sinigaglia, eds SILFS Series Editor Marcello D'Agostino . .-

. _ - _...

_-----

[email protected] ._--

Table of contents

Editors' preface

ix

List of contributors

xi

PART I

LOGIC AND COMPUTING

U MBERTO RIVIECCIO A bilattice for contextual reasoning FRANCESCA POGGIOLESI

Reflecting the semantic features of 85 at the syntactic level GISElLE FISCHER SERVI

Non monotonic conditionals and the concept I believe only A CARLO PENCO! DANIELE PORELLO

Sense and Proof ANDREA PEDEFERRI

Some reflections on plurals and second order logic

1 3

13 27

37

47

G. CASINI, H. HOSNI

Default-assumption consequence relations in a preferential setting: reasoning about normality BIANCA BORET'fI, SARA NEGRI

On the finitlzation of Priorean linear time RICCARDO BRUNI

Proof-theoretic aspects of quasi-inductive definitions

© Individual author and College Publications 2010. All rights reserved. ISBN 978-1-84890-003-5 College Publications Scientific Director: Dov Gabbay Managing Director: Jane Spurr Department of Computer Science King's College London, Strand, London WC2R 2LS, UK http://www.collegepublications.co.uk Cover designed and created by Laraine Welch Printed by Lightning Source, Milton Keynes, UK

AII.rights ~~se.r:'ed. N? part of this publication may be reproduced. stored in a retrieval system

._______ . _ . _ . _0_0_0_. ____0___.

53 67 81

GIACOMO CALAMAI

Remarks on a proof-theoretic characterization of polynomial space functions

PART II

PHYSICS AND MATHEMATICS

95 115

VINCENZO FANO, GIOVANNI MACCHIA

How contemporary cosmology bypasses Kantian prohibition against a science of the universe

117

GIULIA GIANNINI

Poincare and the electromagnetic world picture. For a revaluation of his conventionalism

131

MARCO TOSCANO

"Besides quantiti': the epistemological meaning of Poinc~'s qualitative analysis

141