Metascience (2011) 20:417–442 DOI 10.1007/s11016-010-9465-5 BOOK SYMPOSIUM Scientific representation: A long journey from pragmatics to pragmatics Bas C. van Fraassen: Scientific representation: Paradoxes of perspective. Oxford: Clarendon Press, 2008, xiv+408pp, £35.00 HB James Ladyman • Ota´vio Bueno • Mauricio Sua´rez • Bas C. van Fraassen Published online: 17 November 2010 Ó Springer Science+Business Media B.V. 2010 James Ladyman Once again, van Fraassen has given us an incredibly rich, learned and profound book that will be studied and argued about for decades to come. The book is about scientific representation, but from the perspective of Bas van Fraassen’s empiricism this means ‘‘representation of the empirical phenomena’’ (1). He is keen to distance himself from the empiricist tradition that would interpret the latter notion in terms of mental representation, and instead focuses his attention on mathematical and material representations, and one main form of representation in which he is interested is the representational aspect of measurement. Following and extending the line of argument that we find in the work of Poincare´ and Weyl among others, van Fraassen argues for the ‘‘essential indexical’’ (3) in science. This is a radical view that is at odds with the idea of objective inquiry that enables us to transcend our situation and describe the world independently of human beings, which is how many philosophers, especially scientific realists, see science. van Fraassen’s J. Ladyman (&) Department of Philosophy, University of Bristol, 9 Woodland Rd, Bristol BS8 1TB, UK e-mail: [email protected] O. Bueno (&) Department of Philosophy, University of Miami, Coral Gables, FL 33124, USA e-mail: [email protected] M. Sua´rez (&) Department of Logic and Philosophy of Science, Complutense University of Madrid, 28040 Madrid, Spain e-mail: msuarez@filos.ucm.es B. C. van Fraassen (&) Philosophy Department, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132, USA e-mail: [email protected] 123 418 Metascience (2011) 20:417–442 empiricist and antimetaphysical philosophy permeates his treatment of scientific representation and he repeatedly highlights those aspects of how we draw, describe and measure the phenomena that have to do with our relationship to both the latter and the representations themselves. He argues for subjectivity’s place in our understanding of science and denies that science can ever achieve a fully objective representation of the world. In the light of these observations, it is questionable whether the project of describing how scientific representation works can really be largely orthogonal to the realism/antirealism dispute as van Fraassen claims (3). Van Fraassen did a great deal to reinvigorate the scientific realism debate after the post-positivist repudiation of previously popular forms of instrumentalism. In a much-anthologised chapter of The Scientific Image, he defended the idea that the aim of science is ‘‘to save the phenomena’’. The latter were understood to be the same as the appearances, but there is an important innovation in his thought expressed by the distinction he now draws between the phenomena and the appearances, where the former are observable entities and the latter are the contents of observation or measurement outcomes (8). So, for example, the measurement of temperature (Chapter 5) is to be understood in terms of the distinction between the phenomena associated with heat and the appearances that are saved by scientific theories mapping to representations of the appearances in the form of experimen- tally determined values of temperature. As van Fraassen explains, the construction of appropriate appearances—thermometry—is a rich science in its own right. Here, he cites approvingly the work of Cartwright, Giere and others who have argued that scientific representation must be understood not only at the level of high theory but also in the local domains in which high theory is de-idealised and experimental phenomena are modelled in detail. The distinction between phenomena and appearances is the distinction between what is immediately manifest in experience, and the special kinds of experience that are constructed by scientific experimentation and then codified in the form of ‘‘measurement outcomes’’. Clearly, the appearances will be highly theory laden, as in the case of temperature previously mentioned, and in all the appearances of fundamental physics. Van Fraassen stresses that when a theory is said to ‘‘save the phenomena’’, what this usually means is ‘‘saving the appearances’’. The latter can naturally be understood in terms of structural relationships between representations because the appearances are usually in mathematical form. Consider the case of the planetary orbits and their theoretical representation in Copernicus’ model of the solar system (Chapter 12). Here, the phenomena are the orbits of the planets and the appearances are the perspectival measurements of the positions of particular heavenly bodies in the night sky. Hence, retrograde motion belongs merely to the appearances and is not a genuine phenomenon. Note however that while the phenomena are supposed to be observable, they are only manifest to us in the form of one or other set of appearances (the positions of points of light in the night sky on Earth seen with the naked eye or through a telescope, as opposed to the positions of lights in the night sky seen from the Moon). So are the phenomena inferred and theoretical (though perhaps not usually as much as the appearances)? Van Fraassen would, I think, say not because he insists that the phenomena are observable entities, events and processes. He denies that we can 123 Metascience (2011) 20:417–442 419 reduce the observation of a galloping horse to a series of mental representations with some characteristic content and structure, and then claim that the horse is inferred as the best explanation. Now of course nobody would deny that in our actual cognition the representation of a continuing entity that moves through space is not a matter of inference. It is in philosophical vein when we ask about the source of our knowledge of the horse and what limits there are to that knowledge that indirect or representative realism is tied to the choices we face among competing explanations of the world we see around us. Returning to the case of the night sky, the appearances were once interpreted in very different terms by people who had no inkling of the distinction between planets and stars. The interpretation of the appearances is up for grabs and is only stabilised as the result of sophisticated inference to orbits based on lots of data. What in principle is different between the case of the orbits and the measurements of them, and cells and how they look through a microscope or particle collisions and the tracks they cause in cloud chambers? Measurement outcomes in general ‘‘show not how the phenomena are but how they look’’. However, if how they are must be inferred from how they look, then ultimately that they are must also be so inferred. This may not go for charging horses, but it surely does for the Moon and public objects like gases such as methane, which we can smell, electromagnetic fields, which we can see in the form of sparks and lightning, and so on. Tracks in particle chambers and images in microscopes are public objects, but van Fraassen classifies them as akin to mirages or rainbows, namely as public images. Phenomenologically, he is correct but the objection I have in mind is that the public objects he takes to be part of the realm of the phenomena are as much inferred as theoretical objects. I think we have good reason to believe that the inferences in the case of everyday objects are ones that we are evolutionarily predisposed to make as we are stimulated by the senses in the course of our development. Furthermore, if someone spends the daily life in a physics laboratory, it is unclear what should we count as the everyday things around him or her. Of course, van Fraassen has in the past set great store in the distinction between the unobservable and the merely unobserved, in the sense that horses galloping too far away to see are nonetheless in the realm of the phenomena. His view in the present work is much the same for the phenomena include all the observable entities—events, objects, processes—that there are, have been, or will be, whether observed or measured or not (307, his emphasis). I have argued that the modal status of the observable is a problem for van Fraassen’s empiricism, but whether or not that is correct, it is worth considering also whether his account of scientific representation has aporia related to modality. Van Fraassen argues that represen- tation must be understood contextually and pragmatically in terms of the use or function it has for someone (23). It seems then that he rules out the naturalisation of representation in evolutionary theory and biology more generally. On this view, RNA and DNA do not represent anything unless used by a genetic engineer to do so, and the state of the visual cortex per se does not represent the environment. This is mysterious, for we are told nothing about how human subjects manage to introduce representation out of nowhere. It is also implausible to make representation and subjectivity all-or-nothing and to confine them to human beings. I see no reason to 123 420 Metascience (2011) 20:417–442 deny that animals’ senses represent their environments to them. Representation may concern ‘‘aboutness’’ but if the processing in the visual cortex is not about anything, then why suppose that my words are? In van Fraassen’s view, intentionality seems to be an all-or-nothing matter of which scientific understanding is impossible.