The oncomouse™ is the posterchild of “hybridity.” Along with other transgenic laboratory animals it has gotten considerable attention as a new kind of research object that transgresses the categories of the natural and the artificial, of living organism and constructed thing, of physis and techne. Indeed, any investigation of the ontology of technoscientific objects is likely to begin by pronouncing that these objects are hybrids. However, philosophical analysis has to move beyond this finding and should not mistake it for a profound insight. The transgression of received categorical distinctions can only be an effect that accompanies the ontological character of an object. To say that the oncomouse is simultaneously a living organism and a constructed thing is only to conjure an air of paradox and serves to show that it eludes familiar distinctions which do not therefore have to be surrendered (see Schiemann 2005; compare Dupuy 2010). For all its fame, therefore, the oncomouse still deserves close scrutiny. Only some of its features shall be mentioned here.

The oncomouse is usually considered a “model” but what kind of model is it, and if it is a model, what does this tell us about modeling? Several overlapping distinctions have been proposed – that between animal model and model animal, between being a model of and a model for, between serving as representation of a denoted reality and allowing immersion in a substitute reality (see, e.g., Keller 2000, Gzil 2007, Nordmann 2006). All these distinctions revolve around features of the oncomouse that become salient in different contexts of its design and use. If the mouse is to develop a kind of cancer that also occurs in humans, its design requires a physical correspondence between the human cancer and the mouse cancer, and its designers will therefore be able to account for that correspondence, e.g., by referring to the pertinent genes that are responsible for the expression of the tumor. For the biomedical researchers who study cellular processes and seek ways to suppress tumor development, these questions of correspondence drop out of the picture entirely. Instead, they may well spend their entire career studying the oncomouse, seeking a way to treat cancer in a creature that has been engineered to have that cancer. For these researchers, the oncomouse cancer is not a model of human cancer, just as little as the oncomouse is a model of a human being. For them, the oncomouse is a model for biochemical tinkering, that is, a substitute reality that exhibits certain behaviors which are subject to practical influence – a reality, therefore, to engage with in a sustained, intimate, immersive manner. And yet, this immersive engagement with the material reality of the oncomouse is thought to promote the discovery of therapies for human cancer. What is done for the treatment of the oncomouse is simultaneously for the treatment of the human cancer – not because the genetic structure of the mouse cancer somehow depicts the genetic structure of the human cancer, but on the assumption that the mouse cancer is the human cancer and vice versa: The oncomouse participates in the reality of the human cancer patient. And this may be an important ontological feature of the oncomouse: It is what it is in terms of its physiology and material reality, and beyond that it is also the bearer of a disease process by virtue of the participation, jointly, of mouse and human in a shared reality. The oncomouse as model animal is thus set off from representational models and at the same time moved into the vicinity of computer simulations, experimental systems, and even of the magical thinking that can also be found in voodoo practices.1

All this is further complicated or perhaps amplified by the fact that at least in the case of the oncomouse, this notion of participation cannot be reduced to instantiation: The cancer of the oncomouse is not an instance of human cancer. This becomes evident when one considers the following difference: A human being may have a natural disposition to develop cancer, but the cancer in the mouse is an engineered affordance. The notion of dispositional property to respond to a stimulus-condition supports the work of purification: The external, perhaps technical or environmental stimulus is distinct from the natural or automatic response to that stimulus. In a classical scientific experiment, for instance, the scientists or experimenters actively construct the instrumental set-up and provide a stimulus condition, and then they step back to become mere passive observers of the way in which the system naturally responds to the stimulus. Similarly, if a human being has a disposition to develop cancer, any number of processes or events might serve as stimuli, but once this likely or unlikely event has occurred, it is thought to be in the nature of that human being to develop that cancer. The oncomouse does not instantiate this dynamic. It does not require a stimulus to develop cancer but does so simply through its existence or by its very nature where that nature, however, is specifically designed to suit human research purposes. When a thing delivers an effect, performance, or service to its user, one speaks of an affordance.2 Affordances resist the work of purification: It is in the “nature” of the oncomouse to afford a cancerous tumor just as it is in the “nature” of a bicycle to afford a kind of transport.3

Once the oncomouse is seen as a material system in its own right that participates in the reality of other things, and once this relation is understood as an engineered affordance rather than a mere instantiation of a natural process, one sees how the oncomouse is heavily invested with human values and purposes. This is, indeed, how the oncomouse was popularized by Donna Haraway (1997). Indeed, Haraway suggests that the oncomouse is perhaps not an object of research at all but a subject: The mouse performs a sacrifice for human beings; it was dispatched by us into the war against cancer, and now it acts on our behalf and dies for us in this war. If objectivity consists in gaining a proper distance, the subjectivity of the oncomouse and its investment with human value and purpose presents a challenge to the philosophy of technoscience. If it cannot be secured through intersubjective agreement on detached representations, it must originate in its material character and the technical robustness of its performance.


  1. It might appear far-fetched to speak of “magical thinking“ in respect to technoscientific research practice. But the far-fetched comparison makes a point about inferences from the similarity of two physical systems, e.g., from the similarity of cancer in the oncomouse and a human, or from the similarity of a dynamic behavior in silico and in vivo (of a simulation model in a computer and of a physical process in an experimental system). Precisely because these similarities are constructed with the help of research technologies, one can take them as indicative of a shared reality that makes these systems similar. (Compare to this the skeptical rejection of inferences from similarity in modern theories of knowledge: similarity judgments are thought to be reducible to statements of the form “identical in specific respects, different in other respects” and not to signify anything sui generis – see Goodman1972 in contrast to Foucault 1973, esp. pp. 17-25).
  2. In many cases the outcome of activating a disposition does not depend on any particular human situation, interest, or construction. However, in some cases the phenomenon has a specifically human aspect. Compare the generic outcome that ice of a certain thickness can bear a certain weight per unit area, expressed in a generic disposition, with the claim that ice of that thickness affords walking for a person. Generalizing the notion of an affordance we can say that an apparatus/world complex can afford things. For instance, wheat, yeast, and a stove can afford loaves of bread. A lathe can afford chair legs, and a discharge tube can afford gamma rays.[…] The phenomena that are produced in an [apparatus/world complex] are the manifestations of affordances. These are dispositions that bring together two sets of causal powers that cannot be disentangled. There are the powers of the material stuff organized as an apparatus and the powers of the world realized in the phenomena.“ (Rom Harré 2003, pp. 37f.)
  3. Here the concept of “nature” follows an Aristotelian conception whereby every thing has its own nature and no longer refers to a homogeneous space of lawful regularities.


  • Dupuy, J.-P. (2010). The Narratology of Lay Ethics, Nanoethics, vol. 4(2), pp. 153-170.
  • Foucault, M. (1973). The Order of Things: An Archeology of the Human Sciences. New York: Vintage Books.
  • Goodman, N. (1972). Seven Strictures on Similarity. In: Problems and Projects. Indianapolis, Ind.: Bobs-Merrill, pp. 22-32.
  • Gzil, F. (2007). Animal Models of Alzheimer’s Disease and Cognitive Ageing, Presentation at the First Conference of the European Philosophy of Science Association, Madrid, November 14-17.
  • Haraway, D. (1997). Modest_Witness@Second_Millenium. FemaleMan©_Meets_Onco-Mouse™: Feminism and Technoscience. New York: Routledge.
  • Harré, R. (2003). The Materiality of Instruments in a Metaphysics for Experiments. In: Philosophy of Scientific Experimentation. Radder, H. (Ed), Pittsburgh, PA: University of Pittsburgh Press, pp. 19-38.
  • Keller, E.F. (2000). Models of and Models for: Theory and Practice in Contemporary Biology. Philosophy of Science, vol. 67 (3), pp. 72-86.
  • Nordmann, A. (2006). Collapse of Distance: Epistemic Strategies of Science and Technoscience. Danish Yearbook of Philosophy, No. 41, pp. 7-34.
  • Schiemann, G. (2005). Natur, Technik, Geist. Kontexte der Natur nach Aristoteles und Descartes in lebensweltlicher und subjektiver Erfahrung. Berlin/New York: de Gruyter.