Abstract
The property of being the implementation of a computational structure has been argued to be vacuously instantiated. This claim provides the basis for most antirealist arguments in the field of the philosophy of computation. Standard manoeuvres for combating these antirealist arguments treat the problem as endogenous to computational theories. The contrastive analysis of computational and other mathematical representations put forward here reveals that the problem should instead be treated within the more general framework of the Newman problem in structuralist accounts of mathematical representation. It is argued that purely structuralist and purely functionalist accounts of implementation are inadequate to tackle the problem. An extensive evaluation of semantic accounts is provided, arguing that semantic properties are, unlike structural and functional ones, suitable to restrict the intended domain of implementation of computational properties in such a way as to block the Newman problem. The semantic hypothesis is defended from a number of recent objections.
Similar content being viewed by others
Notes
In particular, they can be argued to belong to a restricted subclass of mathematical dynamical systems. These are abstract structures represented by triplets of the form: \( < T,M,\{ g^{t} \} >, \) where T is the time set, M is the state space and {g t} is the set of state transitions \( \{ g^{t} \} :M \to M \). Abstract computational systems can be argued to belong to this class of mathematical structures. The following is an example of how this can be proved in the case of Turing machines (see Giunti 1995). The future behaviour of a Turing machine is determined when: (1) the state of the internal control unit, (2) the symbol on the tape scanned by the head and (3) the position of the head, are given. It is therefore possible to take the set of all triplets <state, head-position, tape-content> as the state space M of the system; the set of non-negative integers can be taken as the (machine) time set T; the set of quadruples of the machine is then used to form the set {g t} of state transitions. Each state transition function is such that {g 0} is the identity function on M, and \( g^{t + 1} (x) = g(g^{t} (x)) \). Similar considerations apply to all other computational structures.
Following a standard use, the term “implementation” here denotes specifically the realization of computational structures. When referring to the realization of generic mathematical structures (not necessarily computational), I shall use the term “instantiation”.
Attempts to ground the notion of implementation on that of step satisfaction (see for example Cummins 1989: 91–92), for instance, or on the digital vs. analogous distinction (see Haugeland 1981), or on the instantiation of fundamental vs. derivative physical laws (Block and Fodor 1972) have all been argued to fail to make a case for computational realism. For an extensive survey of the various proposals and of their shortcomings see Shagrir (1997).
The technical result, moreover, has been argued to be extendable to the claim that any open physical system implements any automaton. An argument to this effect can be found in Scheutz (1999).
See Melia and Saatsi (2006) for an extensive discussion of the various options.
Cantor's theorem is of course true also in Skolem's countable model.
This does not contradict the thesis that functional accounts are unsuitable, alone, to ground the notion of implementation. The essential role played by functional, mechanistic properties in individuating the relevant computational properties is, I argue, a practical, not a metaphysical one. Here we are concerned with necessary and sufficient conditions for the implementation of computational structures. See the conclusive remarks at the end of this paper for a discussion of the relation that obtains between the various accounts of implementations presented here.
For a detailed analysis of the problem of liberalism in functionalist accounts see Block 1980 and Weir (2001). Weir argues that functionalist accounts based on D. Lewis’ analysis fall prey of the chauvinistic horn of the dilemma, while other accounts fail to block excessively liberal implementations.
See the next section of this paper for a discussion of the philosophical implications of Marr’s theory of vision.
The discovery of this algorithm is due to J. Buntrock and H. Marxen.
The symbols R and L refer to the familiar actions of moving the read/write head one cell to the right or one to the left, respectively.
Indeed it could be argued that we acquire the representations of the numerals, and learn to manipulate them, long before we come to understand what the numerals are intended to represent.
References
Amundson, R. (2000). Against normal function. Studies in the History and Philosophy of the Biological and Biomedical Sciences, 31, 33–53.
Block, N. (Ed.). (1980). Introduction: What is Functionalism? Readings in Philosophy of Psychology (Vol. 1, pp. 171–184). Cambridge, MA: Harvard University Press.
Block, N., & Fodor, J. (1972). What psychological states are not. In N. Block (Ed.), Readings in Philosophy of Psychology (Vol. 1, pp. 237–250). Cambridge: Harvard Press.
Boccardi, E. (2008). Computational externalism, PhD thesis, London School of Economics and Political Science, University of London.
Burge, T. (1986). Individualism and psychology. Philosophical Review, 95, 3–45.
Butler, K. (1996). Content, computation, and individualism in vision theory. Analysis, 56(3), 146–154.
Chalmers, D. (1996). Does a rock implement every finite-state automaton? Synthese, 108, 309–333.
Copeland, J. (1996). What is computation? Synthese, 108, 335–359.
Craver, C. F. (2001). Role functions, mechanisms, and hierarchy. Philosophy of Science, 68(1), 53–74.
Cummins, R. (1989). Meaning and mental representation. Cambridge, MA: MIT Press.
Demopulos, W., & Friedman, M. (1985). Bertrand Russell’s the analysis of matter: Its historical context and contemporary interest. Philosophy of Science, 52(4), 621–639.
Egan, F. (1995). Computation and content. The Philosophical Review, 104(2), 181–203.
Fodor, J. (1980). Methodological solipsism considered as a research strategy in cognitive psychology. The Behavioral and Brain Sciences, III(1), 63–109.
French, S., & Saatsi, J. (2006). Realism about structure: The semantic view and non-linguistic representations. Philosophy of Science, 73, 548–559.
Giunti, M. (1995). Dynamic models of cognition. In T. van Gelder & R. Port (Eds.), Mind as motion (pp. 195–225). Cambridge: MIT Press.
Gould, S. J. (1981). The mismeasure of man. New York: W.W. Norton and Company.
Haugeland, J. (1981). Mind design II. Cambridge, MA: MIT Press/Bradford Books.
Johnson-Laird, P. N. (1988). The computer and the mind. Cambridge, MA: Harvard University Press.
Ketland, J. (2004). Empirical adequacy and ramsification. British Journal for the Philosophy of Science, 55, 287–300.
Lycan, W. G. (1981). Form, function, and feel. Journal of Philosophy, 78, 24–50.
Marr, D. (1982). Vision. San Francisco: W.H. Freeman.
Marr, D., & Hildreth, E. (1980). Theory of edge detection. Proceedings of the Royal Society of London. Series B, 207, 187–217.
McCulloch, W. S., & Pitts, W. H. (1943). A logical calculus of the ideas immanent in nervous activity. Bulletin of Mathematical Biophysics, 5, 115–133.
Melia, J., & Saatsi, J. (2006). Ramseyfication and theoretical content. British Journal of Philosophy of Science, 57, 561–585.
Millikan, R. G. (1989). Biosemantics. The Journal of Philosophy, 86(6), 281–297.
Moore, C. (1980). Unpredictability and undecidability in dynamical systems. Physical Review Letters, 64(20), 2354–2357.
Newman, M. (1928). Mr. Russells causal theory of perception. Mind, 37, 137–148.
Piccinini, G. (2007a). Computing mechanisms. Philosophy of Science, 74, 501–526.
Piccinini, G. (2007b). Computational modeling vs. computational explanation: Is everything a Turing machine and does it matter to the philosophy of mind? Australasian Journal of Philosophy, 85(1), 93–115.
Piccinini, G. (2008). Computation without representation. Philosophical Studies, 137(2), 205–241.
Psillos, S., & Hendry, R. (2007). How to do things with theories: An interactive view of language and models in science. In J. Brzeziñski, et al. (Eds.), The courage of doing philosophy: Essays dedicated to Leszek Nowak (pp. 59–115). Amsterdam: Rodopi. Forthcoming.
Putnam, H. (1975). Mind, language, and reality: Philosophical papers, vol. II. New York: Cambridge.
Putnam, H. (1988). Representation and reality. Cambridge, MA: MIT Press.
Pylyshyn, Z. (1984). Computation and cognition (2nd ed.). Cambridge, MA: MIT/Bradford.
Russell, B. (1927). The analysis of matter. London: Kegan Paul Trench Trubner.
Scheutz, M. (1999). When physical systems realize functions. Minds and Machines, 9(2), 161–196.
Searle, J. R. (1992). The rediscovery of mind. Cambridge, MA: MIT Press.
Shagrir, O. (1997). Two dogmas of computationalism. Minds and Machines, 7, 321–344.
Shagrir, O. (2001). Content, computation and externalism. Mind, 110, 369–400.
Shagrir, O. (2005). The rise and fall of computational functionalism. In Y. Ben-Menahem (Ed.), Hilary Putnam (contemporary philosophy in focus). Cambridge: Cambridge University Press.
Shagrir, O. (2006). Why we view the brain as a computer. Synthese, 153, 393–416.
Skinner, B. F. (1938). The behavior of organisms. Englewood Cliffs: Prentice Hall.
Skolem, T. (1922). Some remarks on axiomitized set theory. In J. van Heijenoort (Ed.) (1967). From Frege to Gödel. A source book in mathematical logic (pp. 290–301). Cambridge, MA: Harvard University Press.
Turing, A. (1950). Computing machinary and intelligence reprinted in mind design II (2nd ed.). Cambridge, MA: MIT Press.
Weir, A. (2001). More troubles for functionalism. Proceedings of the Aristotelian Society, 101(3), 267–294.
Wells, A. J. (1998). Turing’s analysis of computation and theories of cognitive architecture. Cognitive Science, 22(3), 269–294.
Wilson, R. A. (1994). Wide computationalism. Mind, New Series, 103(411), 351–372.
Worrall, J. (1989). Structural realism: The best of both worlds? Dialectica, 43(1–2), 99–124. Reprinted in D. Papineau (Ed.), The philosophy of science (pp. 139–165). Oxford: Oxford University Press.
Author information
Authors and Affiliations
Corresponding author
Additional information
I am indebted to Andrea Bianchi, Peter Clark, Carl Hoefer, the editors of the LSE Philosophy Papers, and two anonymous referees, for useful comments and interesting discussions on previous drafts of this paper. An earlier version of this paper was presented at the LOGOS talks at the University of Barcelona (Spain), and at the Institito de Investigaciones Filosoficas of the Universidad Nacional Autonoma de México, thanks to the audience for their comments.
Rights and permissions
About this article
Cite this article
Boccardi, E. Who’s Driving the Syntactic Engine?. J Gen Philos Sci 40, 23–50 (2009). https://doi.org/10.1007/s10838-009-9085-1
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10838-009-9085-1