Functional Explanation

I consider some hitherto unexplored examples of teleological language in the sciences. In explicating these examples, I aim to show (a) that such language is not the sole preserve of the biological sciences, and (b) that not all such talk is reducible to the ascription of functions. In chemistry and biochemistry, scientists explaining molecular rearrangements and protein folding talk informally of molecules rearranging “in order to” maximize stability. Evolutionary biologists, meanwhile, often speak of traits evolving “in order to” optimize some (...) fitness-relevant variable. I argue that in all three contexts such locutions are best interpreted as shorthands for more detailed explanations which, were we to spell them out in full, would show that the relevant process would robustly converge towards the same end-point despite variation in initial conditions. This suggests that, in biology, such talk presupposes a substantial form of adaptationism. The upshot is that such shorthands may be more applicable in the physical sciences than the biological. (shrink)

The independence problems for functionalism stem from the worry that if functional properties are defined in terms of their causes and effects then such functional properties seem to be too intimately connected to these purported causes and effects. I distinguish three different ways the independence problems can be filled out – in terms of necessary connections, analytic connections and vacuous explanations. I argue that none of these present serious problems. Instead, they bring out some important and over-looked features of functionalism.

In 1993, biologist Margie Profet captured the attention of the popular press with the publication of her radical thesis: menstruation has a function. Traditional theories, she claims, typically view menstruation as a functionless by-product of cyclic flux. The details of Profet's functional account are similarly radical: she argues that menstruation has been naturally selected to defend the female reproductive tract from sperm-borne pathogens. There are a number of weaknesses in Profet's evolutionary analysis. However, I focus on a set of pragmatic (...) problems that arise prior to any details of her evolutionary account. In arguing for the importance of pragmatic considerations, I draw from the linguistic analyses of Nelson Goodman. I conclude that critical investigation of the evolutionary details of Profet's pathogen defense account will be more feasible if and when biologists more frequently feature the female system of pathogen defense in their inductive generalisations. The system needs to be better entrenched before its functional components, such as menstruation, can be thoroughly investigated. (shrink)

Danchin argues that if scientists can reach a level of understanding of genomes, they will be able to resolve the major biological puzzle of the 21st century: the enigma of the living machine that creates the living machine.

I use Carl Gillett’s much heralded dimensioned theory of realization as a platform to develop a plausible part–whole theory. I begin with some basic desiderata for a theory of realization that its key terms should be defined and that it should be explanatory. I then argue that Gillett’s original theory violates these conditions because its explanatory force rests upon an unspecified “in virtue of” relation. I then examine Gillett’s later version that appeals instead to theoretical terms tied to “mechanisms.” Yet (...) I argue that it too violates the desiderata, since it defines realization for mechanisms in terms of two undefined ideas whose explanatory credentials have not been established—“implementation” and “grounds.” Thus I drop those ideas in favor of an explicit constraint that the parts and properties provide a mechanistic explanation. I also distinguish a special mechanistic theory from a preferred general theory that incorporates other kinds of part–whole explanations that target causal powers or capacities. The result is a theory that has the explanatory virtues of mechanistic theories as well as a broader scope desired by Gillett. I also compare the result to a similar idea from Robert Cummins that has been neglected in recent discussions of realization, namely, his general property analysis rather than his functional analysis. Finally, I defend the preferred general theory against possible objections that attempt to show a conflict between metaphysical demands on a theory of realization versus facts about good scientific explanation. (shrink)

Philosophers almost universally believe that concepts of supervenience fail to satisfy the standards for physicalism because they offer mere property correlations that are left unexplained. They are thus compatible with non-physicalist accounts of those relations. Moreover, many philosophers not only prefer some kind of functional-role theory as a physically acceptable account of mind-body and other inter-level relations, but they use it as a form of “superdupervenience” to explain supervenience in a physically acceptable way. But I reject a central part of (...) this common narrative. I argue that functional-role theories fail by the same standards for physicalism because they merely state without explaining how a physical property plays or occupies a functional role. They are thus compatible with non-physicalist accounts of that role-occupying relation. I also argue that one cannot redeploy functional-role theory at a deeper level to explain role occupation, specifically by iterating the role-occupant scheme. Instead, one must use part-whole structural and mechanistic explanations that differ from functional-role theory in important ways. These explanations represent a form of “superduperfunctionalism” that stand to functional-role theory as concepts of superdupervenience stand to concepts of supervenience. (shrink)

Over the last 20 years, several philosophers have developed a new approach to biological functions, the organizational approach. This is not a single theory but a family of theories based on the idea that a trait token can acquire a function by virtue of the way it contributes to a complex, organized system and thereby to its own continued persistence as a token. I argue that the organizational approach faces a serious liberality objection. I examine three different ways organizational theorists (...) have tried to avoid that objection and show how they fail. (shrink)

This article presents a distinct sense of ‘mechanism’, which I call the functional sense of mechanism. According to this sense, mechanisms serve functions, and this fact places substantive restrictions on the kinds of system activities ‘for which’ there can be a mechanism. On this view, there are no mechanisms for pathology; pathologies result from disrupting mechanisms for functions. Second, on this sense, natural selection is probably not a mechanism for evolution because it does not serve a function. After distinguishing this (...) sense fromsimilar explications of ‘mechanism’, I argue that it is ubiquitous in biology and has valuable epistemic benefits. (shrink)

Despite the voluminous literature on biological functions produced over the last 40 years, few philosophers have studied the concept of function as it is used in neuroscience. Recently, Craver (forthcoming; also see Craver 2001) defended the causal role theory against the selected effects theory as the most appropriate theory of function for neuroscience. The following argues that though neuroscientists do study causal role functions, the scope of that theory is not as universal as claimed. Despite the strong prima facie superiority (...) of the causal role theory, the selected effects theory (when properly developed) can handle many cases from neuroscience with equal facility. It argues this by presenting a new theory of function that generalizes the notion of a ‘selection process’ to include processes such as neural selection, antibody selection, and some forms of learning—that is, to include structures that have been differentially retained as well as those that have been differentially reproduced. This view, called the generalized selected effects theory of function, will be defended from criticism and distinguished from similar views in the literature. (shrink)

La discusión acerca de funciones es de larga data en filosofía. Normalmente se describe a la revolución científica del siglo XVII como eliminando las causas finales y la teleología de la física. Sin embargo, el lenguaje funcional cumple un papel central en ciertas áreas de la práctica biológica. Esto ha llevado a muchos filósofos a intentar elucidar el concepto de función, en algunos casos para defender la relevancia de estos usos, en otros para mostrar que se trata de meras formas (...) de hablar que podrían ser eliminadas sin pérdida de ningún tipo de información relevante. El objetivo principal de este trabajo es mostrar la necesidad de apelar a conceptos funcionales para una reconstrucción adecuada de la teoría de la selección natural darwiniana. Pues, se utiliza lenguaje funcional en la conceptualización del campo de aplicación de esta teoría, y tal campo debe ser determinable con independencia la teoría de la selección natural. (shrink)

What is the biological function of perception? I hold perception, especially visual perception in humans, has the biological function of accurately representing the environment. Tyler Burge argues this cannot be so in Origins of Objectivity (Oxford, 2010), for accuracy is a semantical relationship and not, as such, a practical matter. Burge also provides a supporting example. I rebut the argument and the example. Accuracy is sometimes also a practical matter if accuracy partly explains how perception contributes to survival and reproduction.

We discuss explanation of an earlier event by a later event, and argue that prima facie cases of backwards event explanation are ubiquitous. Some examples: (1) I am tidying my flat because my brother is coming to visit tomorrow. (2) The scarlet pimpernels are closing because it is about to rain. (3) The volcano is smoking because it is going to erupt soon. We then look at various ways people might attempt to explain away these prima facie cases by arguing (...) that in each case the 'real' explanation is something else. We argue that none of the explaining-away strategies are successful, and so any plausible account of explanation should either make room for backwards explanation, or have a good story to tell about why it doesn't have to. (shrink)

Both von Neumann and Wiener were outsiders to biology. Both were inspired by biology and both proposed models and generalizations that proved inspirational for biologists. Around the same time in the 1940s von Neumann developed the notion of self reproducing automata and Wiener suggested an explication of teleology using the notion of negative feedback. These efforts were similar in spirit. Both von Neumann and Wiener used mathematical ideas to attack foundational issues in biology, and the concepts they articulated had lasting (...) effect. But there were significant differences as well. Von Neumann presented a how-possibly model, which sparked interest by mathematicians and computer scientists, while Wiener collaborated more directly with biologists, and his proposal influenced the philosophy of biology. The two cases illustrate different strategies by which mathematicians, the “professional outsiders” of science, can choose to guide their engagement with biological questions and with the biological community, and illustrate different kinds of generalizations that mathematization can contribute to biology. The different strategies employed by von Neumann and Wiener and the types of models they constructed may have affected the fate of von Neumann’s and Wiener’s ideas – as well as the reputation, in biology, of von Neumann and Wiener themselves. (shrink)

The Emergic Cognitive Model (ECM) is a unified computational model of visual filling-in based on the Emergic Network architecture. The Emergic Network was designed to help realize systems undergoing continuous change. In this thesis, eight different filling-in phenomena are demonstrated under a regime of continuous eye movement (and under static eye conditions as well). -/- ECM indirectly demonstrates the power of unification inherent with Emergic Networks when cognition is decomposed according to finer-grained functions supporting change. These can interact to raise (...) additional emergent behaviours via cognitive re-use, hence the Emergic prefix throughout. Nevertheless, the model is robust and parameter free. Differential re-use occurs in the nature of model interaction with a particular testing paradigm. -/- ECM has a novel decomposition due to the requirements of handling motion and of supporting unified modelling via finer functional grains. The breadth of phenomenal behaviour covered is largely to lend credence to our novel decomposition. -/- The Emergic Network architecture is a hybrid between classical connectionism and classical computationalism that facilitates the construction of unified cognitive models. It helps cutting up of functionalism into finer-grains distributed over space (by harnessing massive recurrence) and over time (by harnessing continuous change), yet simplifies by using standard computer code to focus on the interaction of information flows. Thus while the structure of the network looks neurocentric, the dynamics are best understood in flowcentric terms. Surprisingly, dynamic system analysis (as usually understood) is not involved. An Emergic Network is engineered much like straightforward software or hardware systems that deal with continuously varying inputs. Ultimately, this thesis addresses the problem of reduction and induction over complex systems, and the Emergic Network architecture is merely a tool to assist in this epistemic endeavour. -/- ECM is strictly a sensory model and apart from perception, yet it is informed by phenomenology. It addresses the attribution problem of how much of a phenomenon is best explained at a sensory level of analysis, rather than at a perceptual one. As the causal information flows are stable under eye movement, we hypothesize that they are the locus of consciousness, howsoever it is ultimately realized. (shrink)

In this paper we examine the following problems: How many concepts of function are there in biology, social science, and technology? Are they logically related and if so, how? Which of these function concepts effect a functional explanation as opposed to a mere functional account? What are the consequences of a pluralist view of functions for functionalism? We submit that there are five concepts of function in biology, which are logically related in a particular way, and six function concepts in (...) social science and technology. Only two of them may help effect a genuine functional explanation. Finally, our synthetic approach allows us to distinguish four different varieties of functionalism in biology, psychology, social science, and technology: formalist, black boxist, adaptationist, and teleological. And only one of them is explanatory in the strong sense defended here. (shrink)

Finality, design and purpose have started to be excluded from the language of the natural sciences since the XVIIth century. Darwin succeeded in excluding them from his theory of evolution appealing to a blind and mechanical natural selection. Today, the most usual definitions for the concept of biological function take for granted that functions: 1) are not dependent on a goal; 2) are not dependent on observers, but only on nature; 3) are explicable in causal terms, either with reference to (...) the causal history of the organ (etiological definition), or with reference to its present structure and causal capabilities (dispositional definition). However, we shall see that such presuppositions cannot take into account the normative character of the concept of biological function. We show that a generalization of the concept of scientific objectivity lets us affirm that functions: 1’) are dependent on a goal; 2’) are dependent on both observers and nature; 3’) cannot be reduced to causality, nor break the laws of physics; and yet, 4) are truly objective. (shrink)

In ‘A modal theory of function’, I gave an argument against all existing theories of function and outlined a new theory. Karen Neander and Alex Rosenberg argue against both my negative and my positive claim. My aim here is not merely to defend my account from their objections, but to (a) very briefly point out that the new account of etiological function they propose in response to my criticism cannot avoid the circularity worry either and, more importantly, to (b) highlight, (...) and attempt to make precise, an important feature of my modal theory that may have been understated in the original paper – that function attributions depend on the explanatory project at hand. (shrink)

I clarify some of the details of the modal theory of function I outlined in Nanay (2010): (a) I explicate what it means that the function of a token biological trait is fixed by modal facts; (b) I address an objection to my trait type individuation argument against etiological function and (c) I examine the consequences of replacing the etiological theory of function with a modal theory for the prospects of using the concept of biological function to explain mental content.

The function of a trait token is usually defined in terms of some properties of other (past, present, future) tokens of the same trait type. I argue that this strategy is problematic, as trait types are (at least partly) individuated by their functional properties, which would lead to circularity. In order to avoid this problem, I suggest a way to define the function of a trait token in terms of the properties of the very same trait token. To able to (...) allow for the possibility of malfunctioning, some of these properties need to be modal ones: a function of a trait is to do F just in case its doing F would contribute to the inclusive fitness of the organism whose trait it is. Function attributions have modal force. Finally, I explore whether and how this theory of biological function could be modified to cover artifact function. (shrink)

It is certainly true that in early modern thought the emergence of a new science changed the image of the universe in a mechanistic way. It must be considered, though, that most of the main protagonists of this revolution (Kepler, Newton, Leibniz, ‘biologists’ like Leeuwenhoek, Hartsoeker, Hooke, Malpighi, Redi, etc.) still continued to consider the importance and the utility of a finalistic explanation of natural phenomena. Concepts like “function”, “self-organization”, “organism” have roots in early modern thought: not only from a (...) linguistic and semantic point of view. They were the basis of an epistemology in which different kinds of categories are strictly related. Aim of the paper is to take into account the relevance of the mechanical explanation of natural phenomena in Leibniz’s thought and at the same time to highlight the polarization between mechanical explanations and finalistic consideration that emerges in his philosophy. The specific aim of the paper is to analyze and to develop this kind of dialectic between “teleology” and "mechanism", with particular reference to the concept of “living being”. (shrink)

B. F. Skinner's claim that "operant behavior is essentially the field of purpose" is systematically explored. It is argued that Charles Taylor's illuminating analysis of the explanatory significance of common-sense goal-ascriptions (1) lends some (fairly restricted) support to Skinner's claim, (2) considerably clarifies the conceptual significance of differences between operant and respondent behavior and conditioning, and (3) undercuts influential assertions (e.g., Taylor's) that research programs for behavioristic psychology share a "mechanistic" orientation. A strategy is suggested for assessing the plausibility of (...) Skinner's broader claims about the adequacy of the operant behaviorist program for the analysis of purposive behavior. (shrink)

There is a debate in philosophy of mind about the nature of reason explanations of action, and this volume is testament to a resurgence of interest in non-causal accounts. In Teleological Realism: Mind, Agency, and Explanation,2 I have proposed a non-causal account according to which common-sense reason explanations of action are irreducibly teleological in form. I claim that we explain behavior by citing the state of affairs towards which the agent was directing her behavior, i. e., by citing the purpose (...) or goal of the behavior. I will not be defending that account of action explanation here, but will be assuming it and applying it to the free will debate. I will argue that the teleological account of action explanation leads to a view of free will with some interesting and attractive features. Philosophical accounts of free will typically propose some sort of criterion for determining which behaviors count as free, e. g., that the agent could have done otherwise, or that the behavior was in accord with the agent’s second-order volitions. The account is then usually used to answer the question of whether we have free will, and especially whether we can have free will even if determinism is true. To test these accounts, philosophers make arguments of various sorts, but the primary method is with cases. Here’s the recipe for an objection to an account of free will: come up with a case where the theory says that the agent is free, but our intuition says that the agent is unfree, or vice versa. I won’t question the method of cases in principle; it’s what we have and it makes some sense. On the picture of analytic philosophy as conceptual analysis, it makes perfect sense. Philosophers put forward a precisely spelled out version of our concept of free will; but if such an account is at odds with firm intuitions in particular cases, then it can’t be what we mean. We know that the situation is not really so simple as that. Our ordinary concept of free will might be messy and not perfectly consistent; accordingly, any particular theory might get a few cases ›wrong‹ as judged by our intuitions.. (shrink)

Starting with Aristotle and moving on to Darwin, Marco Solinas outlines the basic steps from the birth, establishment and later rebirth of the traditional view of living beings, and its overturning by evolutionary revolution. The classic framework devised by Aristotle was still dominant in the 17th Century world of Galileo, Harvey and Ray, and remained hegemonic until the time of Lamarck and Cuvier in the 19th Century. Darwin's breakthrough thus takes on the dimensions of an abandonment of the traditional finalistic (...) theory. It was a transition exemplified in the morphological analysis of useless parts, such as the sightless eyes of moles, already discussed by Aristotle, which Darwin used as a crowbar to unhinge the systematic recourse to final causes. With many excerpts, a chronological sequence and an analytical approach, this book follows the course of the two conceptions that have shaped the destiny of life sciences in western culture. (shrink)

Historical accounts of biological function are thought to have, as a point in their favour, their being able to accommodate malfunction. Recently, this has been brought into doubt by Paul Sheldon Davies’s argument for the claim that both selected malfunction (that of the selected functions account) and weak etiological malfunction (that of the weak etiological account), are impossible. In this paper I suggest that in light of Davies’s objection, historical accounts of biological function need to be adjusted to accommodate malfunction. (...) I propose a historical account which places two conditions on membership of a functional kind. My claim is that it is in virtue of a trait’s meeting these conditions that it is a member of a functional kind, and can thus malfunction. I suggest that a version of my proposal can be adopted by both the selected effects and weak etiological theorists, and so conclude that such a proposal meets Davies’s objection. (shrink)

John Searle has argued that functions owe their existence to the value that we put into life and survival. In this paper, I will provide a critique of Searle’s argument concerning the ontology of functions. I rely on a standard analysis of functional predicates as relating not only a biological entity, an activity that constitutes the function of this entity and a type of system but also a goal state. A functional attribution without specification of such a goal state has (...) no truth-value. But if completed with a goal state, functional attributions understood as four-place relations attain a truth-value. The truth conditions of all attributions of function involve a dependence claim of the goal state on the function bearer’s activity. The nature of this dependence may differ; I consider five different possibilities: causality, mechanistic constitution, mereology, supervenience and metaphysical grounding. If these dependency relations are objective, Searle’s central ontological thesis fails. What he ought to have said is that our valuing survival or other goal states may be the reason why biology seeks functional knowledge, but this has nothing to do with ontology. I will show further that Searle also raised an interesting challenge concerning the relationship of functional and causal truths, but it does not threaten the objectivity of functions either. At best, it could show that functional vocabulary is eliminable. However, I will show that functional vocabulary is not so eliminable. (shrink)

Im Zuge der Entwicklung der Synthetischen Biologie lassen sich zur Zeit in den modernen Lebenswissenschaften Bemühungen erkennen, Leben künstlich herzustellen. Die vorliegende Arbeit befasst sich mit den erkenntnistheoretischen Aspekten der Versuche einer technischen Erzeugung von minimalen Lebensformen. Sie untersucht, auf welchen unterschiedlichen Grundannahmen die aktuellen Projekte zur Herstellung von Proto- und Minimalorganismen beruhen bzw. welche Eigenschaften von Organismen als konstitutiv für die Lebensprozesse angenommen werden.

Review of Peter Mc. Laughlin *What Functions Explain" (2001).