John Michael
University of Vienna
Initiativkolleg: Die Naturwissenschaften im historischen Kontext
john.michael@univie.ac.at
November 2007
Simulation as an epistemic tool between theory and practice:
A Comparison of the Relationship between Theory and Simulation in Science
and in Folk Psychology
0. Introduction
In this paper, I give reasons for the emergence of a consensus that the two
competing accounts of folk psychology – namely, simulation theory and theorytheory – must be combined in order to develop a satisfactory theory of everyday
psychological competence. After giving a bit of background on and criticism of
simulation theory and theory-theory in the first section, I go on in the second
section to pursue the analogy to science that the names of both theories invite.
Specifically, I defend the thesis that the analogy to simulations in science shows
us how theoretical elements in folk psychology can be complemented by (i.e. not
replaced by) the central idea of simulation theory – namely that our own
cognitive habits and dispositions provide us with a resource that is distinct from
propositional knowledge in folk psychology. That is a descriptive point of
psychology. In section three, I inquire whether the analogy to simulations in
science can help us to appreciate the relevance of the folk psychology debate for
epistemological and ontological questions about mental states. I argue that our
use of simulations during cognitive development enables us to imitate the people
around us and thereby to become more similar to them, which in turn makes
simulation an increasingly effective epistemic strategy. Insofar as theoretical
elements – such as the distinctions, relations, and entities referred to in folk
psychological discourse – play a role in imitative learning, they are causally
embedded in our cognitive development, so we have good reason to regard them
as being among the real causes of our behavior.
I. The context of the discussion about simulation theory in the philosophy of
mind
Theory-theory was the more-or-less unchallenged view of folk psychology until
the late 1980’s (although it did not come to be called theory-theory until
simulation theory arose as an alternative).1 According to theory-theory, which is
prominently supported by (among others) Josef Perner, Alison Gopnik and
Simon Baron-Cohen, folk psychology is a largely unconscious theory including
theoretical entities (mental states such as beliefs and desires) and general
psychological laws linking them to each other and to behavior. Since mental
states, on this view, are defined by their functional relations, theory-theory is the
natural counterpart to functionalism in the philosophy of mind.
According to simulation theory, on the other hand, folk psychology is a
practice whereby we put ourselves into others’ shoes and simulate their situation
from our own perspective. The “radical” version espoused by Robert Gordon
denies that either psychological laws or mental concepts are generally employed
in folk psychological prediction.2 One of the other main advocates of simulation
theory, Alvin Goldman, accepts that mental concepts play a role in simulations,
insofar as one must identify one’s own mental state upon completing the
simulation procedure before one can ascribe it to another person. But he differs
form the theory-theorists in that he claims that there is an introspective
component to mental concepts that cannot be captured by their functional roles.
Moreover, in deriving a prediction of someone’s action from their input states,
1
The debate has been in full swing since the publication of two volumes in the mid-nineties
that collected articles by proponents of both positions: Carruthers, P. & Smith, P., eds., 1996,
Theories of Theories of Mind. Cambridge: Cambridge University Press; Davies, M. and Stone
T., eds., 1995, Folk Psychology: The Theory of Mind Debate. Oxford: Blackwell Publishers.
The introductory chapter of the latter offers an excellent overview and analysis of the initial
debate.
2
Gordon, R., 1995, "Simulation Without Introspection or Inference From Me to You," in
Mental Simulation: Evaluations and Applications, M. Davies & T. Stone (eds.), Oxford:
Blackwell.
one employs the same procedures that the target person employs (e.g. practical
reasoning), and not separate folk psychological inferential procedures. 3
One problem with simulation theory is that it is simply quite diffuse.
Different people mean different things when they talk about simulations. Some
propose that in folk psychology we actually imagine ourselves in another
person’s situation in order to understand or to predict their behavior. I think it is
plausible that we do this sometimes, but we do not seem to do it actively all the
time. So what else could simulation mean in this context? Some proponents
appeal to motor resonance phenomena, i.e. mirror neurons. There are certain
kinds of neural activity that are present when we observe or perform an action.
So it seems that perceiving an action may involve some of the same
physiological processes as performing an action.4 For simulation theory, this
would mean that we correctly anticipate the continuation of someone’s actions
simply because we ourselves would continue them in the same way. But this
kind of simulation would then always be involved in perception, so there would
be no additional process beyond perception that should be called a simulation.
Despite this diversity, what is common to simulationists’ accounts is their
assertion that our own first-person experiences, habits, and dispositions provide
us with a resource other than propositional knowledge that we can use in
explaining and predicting others’ behavior.
Both simulation theory and theory-theory have other problems to deal
with as well. The strongest objection to simulation theory is that simulations
cannot work insofar as we are relevantly different from others. So we need to
identify the ways in which a target person differs from us in order to set the
appropriate parameters. This arguably requires mastery of mental concepts
3
Both of these points are spelled out in Goldman, Alvin, 2006: Simulating Minds: the
philosophy, psychology and neuroscience of mindreading, New York: OUP. For the
introspectionist account of mental concepts, see chapter 9.
4
Cf. for example: Gallese, V., 2001, "The ‘shared manifold’ hypothesis: from mirror neurons
to empathy," Journal of Consciousness Studies, 8, 33-50. Gallese, V., & Goldman, A., 1998,
"Mirror neurons and the simulation theory of mind-reading," Trends in Cognitive Sciences, 2,
493-501.
defined functionally by their nomological relations among each other and to
behavior, since our own beliefs, desires, habits etc. prima facie can’t be of much
use to us in figuring out to what extent other people have different beliefs,
desires, habits, etc. So we are left with no alternative to inferring their beliefs
and desires from their behavior and from what we know about their perceptions.
I don’t want to rule out the possibility that there are ways of dealing with this
problem within a simulationist account5, but most people agree at least that it
presents a problem. On the other hand, there are some fairly persuasive
arguments to the effect that theory-theory cannot work without incorporating
elements of simulation theory, i.e. our own habits and dispositions. I will
mention three briefly:
1. Belief formation on the basis of perception: It seems reasonable that in
figuring out what beliefs other people form about a situation on the basis of
perceptions, we have to incorporate our own perceptions. I can’t imagine how
we could get around using this kind of use of simulation.
2. The Frame Problem: There is a lot of sensory information and also a complex
web of beliefs and desires. How do we pick out the ones that are relevant in a
specific case? Our own intuitions are a better guide than any formal technique as
yet worked out by AI.6
3. Rationality: It is argued by some simulation theorists (in particular Jane
Heal7) that a formal theory of rationality could not replace our own intuitions
about what is rational. This can be significant for folk psychology in numerous
ways. One point is that a theory could not capture the normativity that is
inherent in our conception of rationality. We do not always know what follows
from our beliefs; we sometimes have inconsistent beliefs; we have to make an
5
Gordon thinks it can be dealt with better within a simulationist account than a theory-theory
account, Cf. Gordon, Robert, "Folk Psychology as Mental Simulation”, The Stanford
Encyclopedia of Philosophy (Winter 2003 Edition), Edward N. Zalta (ed.), URL =
<http://plato.stanford.edu/archives/win2003/entries/davidson/>
6
This argument is worked out by Jane Heal in “Simulation, Theory and Content”, in: P.
Carruthers & P.K. Smith, 1996: Theories of Theories of Mind, Cambridge: CUP, p. 75-89
7
This one, too.
effort to be consistent and are sometimes corrected, we exchange reasons to
defend
our
inferences.
Our
judgments
of
rationality
are
therefore
underdetermined by any formal account. So, insofar as we expect others to
behave rationally, we have to rely on our own intuitions about what is rational.
A second point is that the prediction of rational behavior in any given case
concerns not just principles of rationality, but the application or interpretation
of these principles in novel cases. So what we would need is a theory that
explains people’s interpretation of the theory of rationality; and this theory
would in turn have to be interpreted as well, etc. To avoid the regress, we have
to use our own intuition about what is rational. A weaker form of the same
argument would be that we always have novel constellations of beliefs and
desires, so if we are to use principles to decide what follows from them the
danger is that we need new principles for every novel case, and such principles
are no principles at all.
The upshot is that it is unclear whether either simulation theory or theorytheory can really stand on its own. Indeed, this conclusion reflects the consensus
that has emerged. So, given that the two accounts have to be combined, my next
question is whether a look at the way in which theory is combined with
techniques, practices, experiment, traditions, etc. in constructing simulations in
science can help us to figure out how other resources, including mental concepts
and psychological generalizations, are combined with something akin to
simulation in folk psychology.
II. Of what use is the concept of simulation in the empirical-psychological
study of folk psychology?
First, a couple of general observations. In any kind of simulation in science,
theory is required in various ways, but still the simulation can tell us more than
the theory alone. So, if theoretical elements have to be added to simulation
theory to make it work, this does not imply a collapse of simulation theory into
theory-theory. And conversely, the analogy to science should teach us that it
should be no surprise that theory-theory in folk psychology needs to be enriched
by something beyond theory, such as models or simulations.
Given that simulations in science involve/ presuppose some theoretical
elements, a natural question to frame the discussion is: when does simulation go
beyond theory? In addressing this question, I will draw upon Eric Winsberg’s 8
discussion of the ways in which simulations are more like experimental practice
than theory. He makes two main points:
1) We employ a variety of techniques to derive inferences from them (e.g. data
analysis, looking at results across a broad range of parameters, visualization)
2) Our judgment of the reliability of simulations depends upon our successful
application of them and our successive improvement of them within practical
contexts. In this connection, Winsberg refers to Hacking’s dictum: “Experiments
have a life of their own”.9
The link to Hacking suggests four characteristics of the relationship
between simulation and theory in science that I think can be fruitfully applied to
the folk psychology discussion.
1. The construction and use of a simulation can involve numerous theories (in
modeling the target system, in building the instruments). In folk psychology,
much goes into making us similar enough to others to be used as models of
them. For starters, evolution replaces much background theory. But this is not
the whole story: In development we learn knowledge about the world, different
people’s roles, typical narratives, and also psychological concepts like belief and
desire. All of these elements go into making our habits and dispositions similar
to the people around us, but: they do not constitute a single theory.
Winsberg, Eric, 2003: “Simulated Experiments: Methodology for a virtual world”,
Philosophy of Science, 70, p. 105-125.
9
Hacking, Ian, 1983: Representing and Intervening: introductory topics in the philosophy of
science, New York: Free Press.
8
2. Theoretical elements need not be actively invoked by the technician using a
simulation. Indeed, she
may not even know much about them. In folk
psychology, I may use abbreviated syllogisms such as:
“Tom is angry at Paul. He is going to hit Paul.”
There is no reason to insist that I must unconsciously go through a more
complete derivation involving all the trappings of formal logic. I can get away
with using the abbreviated form simply because the observations and inductions
that justify the inference occurred during my developmental history. In fact, I
can even employ true generalizations that I have learned from others without
myself ever having made the requisite observations: that is a benefit of cultural
evolution.
3. Theoretical insights in science may not immediately yield the local
predictions we want, but are used to create models or simulations, which are
then tweaked over time with the addition of new knowledge and techniques,
including rules of thumb for which there is no theoretical justification (e.g. for
simplifying calculations, for setting parameters) until we learn how to use and
interpret them in particular contexts, etc. Similarly, in folk psychology we add
our increasing knowledge about the world, different people’s roles, typical
narratives, and also psychological concepts to our apparatus as we go along.
Moreover, we have to learn to apply these elements by combining them with the
right simulations. For example, it could be argued that predicting behavior on
the basis of a false belief involves a concept of belief plus a simulation. The idea
would be that once I have figured out what beliefs someone has, the only (or the
usual) way to get from the beliefs (in combination with desires and much else of
course) to a prediction of action is to imagine I had those beliefs and see what I
would do.
4. Applying simulations helps us to gain theoretical insights which, in turn, help
us to improve the simulation system. In folk psychology, one can draw a useful
analogy to children’s imitative learning. From a very early age, children imitate
novel movements and even actions – often with less than complete
understanding of the intention guiding the action.10 In so doing, they learn new
actions and become acquainted with new intentions (i.e. goals and strategies for
achieving those goals). Around nine months, when they begin showing signs of
a more sophisticated understanding of their own agency, their imitative behavior
increases dramatically11. This suggests that they are using their own recalled
experiences of performing actions as a heuristic basis with which they gain a
foothold upon adults’ actions. But the interpretation of this data is still
controversial. At any rate, through imitation they learn the habits and
dispositions that are typical of the members of their culture, which leads to their
being cognitively structured in a way similar to the people around them. The
result of this is twofold: they can explain and predict others’ behavior more
effectively by simulating them, and their behavior can in turn be explained and
predicted simulatively by other members of their culture.
III. Of what use is the concept of simulation in the discussion of folk
psychology in the philosophy of mind?
The analogy to science helps not only in developing a descriptive account that
combines theoretical elements with habits and dispositions that are not
characterizable as propositional knowledge, but also in bringing out the
10
Meltzoff and Tomasello are the two most prominent researchers in this context: Cf. for
example, Meltzoff, Andrew N., 2005, „Imitation and other minds: The “Like Me Hypothesis“,
in S.
Hurley, N. Chater (Ed.), Perspectives on Imitation: From Neuroscience to Social
Science Vol.2, Cambridge, MA: MIT, pp. 55-77; Tomasello, Michael, 1999, The cultural
origins of human cognition, Cambridge, Mass.: Harvard University Press.
11
Michael Tomasello speaks of the nine-month revolution in this connection: Tomasello,
Michael, 1999, The Cultural Origins of Human Cognition, Cambridge: Harvard University
Press.
epistemological issues about minds that make this discussion interesting to
philosophers.
It is rather curious that the analogy to science has really only been
exploited by advocates of theory-theory in articulating their position – generally
either functionalism or eliminativism, depending upon whether one considers
folk psychology to be a good theory. Simulation theorists, on the other hand,
have not done so, although the very name of simulation theory suggests the
possibility of maintaining the continuity between folk and scientific psychology
while introducing resources that are of a more practical nature than the
theoretical elements postulated by theory-theorists. I think that this is because a
different approach has appeared more tempting, namely to suppose that the shift
to simulation as an explanation of folk psychological competence undermines
the very discussion of the reducibility of mental state terms (and hence the
relationship between folk psychology and scientific psychology), since doing
justice to our everyday folk psychological competence on a simulationist
account does not require us to take mental states seriously. In simulating others’
decision-making processes, we putatively do not need to think about mental
states or psychological laws in which mental states figure. Note: this does not
necessarily mean that simulation theory is good news for physicalism; on the
contrary, it could suggest some kind of dual aspect theory.
This is all fine and good insofar as it means that we can make our folk
intuitions about minds compatible with scientific psychology simply by
interpreting them in a less robust way. But I think we can take this approach one
step further if we pursue the analogy to science after all, and simply expand the
parameters of the comparison to include not only theoretical elements but also
the various practical resources and the history of practical applications with
which theoretical elements are intertwined.
Again, Ian Hacking’s treatment of experimental practice within the debate on
scientific realism suggests an interesting way to cash out on the analogy
between folk psychology and science (now on an epistemological level).
Hacking asserts that the history of practical application and refinement of
scientific equipment and models (and, I would add, simulations) gives us reason
to think that they are linked up with the world in a systematic way that has
epistemic import. Analogously, I would argue the following: the distinctions
that we make in folk psychological discourse (between propositional attitudes
such as believing, wanting, and fearing) guide us during development in
imitating others and thereby learning from them and becoming more similar to
them. One result, of course, is that we become ever-more reliable simulation
systems. But the flipside of this is even more interesting: since in cognitive
development we use folk psychological notions (such as goals, strategies, beliefs
and desires, and attentional states) to guide our simulations (either in actually
imitating others or in trying to understand what they are up to), we become
increasingly similar to other people as they appear to us when we employ folk
psychology (understood as a combination of theoretical elements and
habits/dispositions). So other people will be able to effectively employ the same
sort of folk psychological resources upon us. In short, the role of folk
psychology in cognitive development ensures that it will be an effective way of
predicting and explaining others’ behavior.
Thus, there is good reason to believe that the distinctions referred to in
folk psychology reflect real structures among the psychological causes of our
behavior.
Insofar as the way in which we employ mental concepts in giving
psychological explanations is intertwined with simulations, (i.e. habits and
dispositions) during development, the latter could be an irreplaceable resource
for scientific psychology. This means that simulation theory (surprisingly) gives
us reason to think that mentalist description is not only compatible with
scientific psychology, but is indeed potentially useful as such to scientific
psychology. So, if you like Hacking’s entity realism, you should also consider
becoming a realist about mental states.