Working on the intersections of science and literature, N. Katherine Hayles, who has postgraduate degrees in both chemistry and literature, has always been concerned with combining the two cultures of the sciences and the humanities. Her work engages with literary and scientific texts with equal rigour, understanding both as struggling with the representational medium of language to create the world they see. Her early work focused on the implications of relativity theory for the relationship between observer and world; more recently, she has considered the future of narrative and reading in a digital age. Throughout, she has explored the importance of medium to our understanding of narrative form and to our conceptualisations of the human subject. She is important to sf studies because of her emphasis on the mutual co-evolution of humans and machines: we engineer machines but our interactions with them simultaneously re-engineer what it means to be human. Her work on the posthuman could be usefully extended to the many robots, cyborgs, AIs and transgenic subjects found in sf film and television, and her work on the media-specific analysis required for electronic narratives suggests provocative ways for thinking about the increasing use of digital technologies in film and television.In The Cosmic Web: Scientific Field Models and Literary Strategies in the 20th Century (1984), Hayles considers relativity theory and modernist narrative, applying 'field theory' to fiction by Robert Pirsig, D. H. Lawrence, Vladimir Nabokov, Jorge Luis Borges and Thomas Pynchon. Field theory attempts to grasp the dynamic relationship between parts and the whole. It requires us to take seriously the Einsteinian principle that the laws of physics can be observed only relative to the position of the observer, and thus the observer is necessarily a part of the system observed rather than an abstract and universally neutral position. Hayles struggles with metaphors to convey a notion of field theory (the 'cosmic web', a 'cosmic dance', a 'network of events', an 'energy field'), each of which implies a reality with no detachable, enduring or unchanging parts. Composed not of particles but of events constantly in motion, the field is rendered dynamic by interactions that are simultaneously affecting each other. The observer is an integral participant in its harmonious, rhythmic patterns. Hayles uses the 'field' as a way to approach what in other contexts would be called poststructuralist semiotics. For her, it helps us to see that language is necessarily a part of the system (the world) it describes, and its refusal to separate subject from object thus enables us to recognise that language constructs rather than describes reality.Hayles encourages us to see her chosen writers' experiments with narrative (and the entanglement of reader and writer, text and world) as part of a larger cultural shift that was also shaping the sciences' understanding of our relationship to the world. She does not argue for causal connections between the similar ideas emerging in physics and in structuralist and poststructuralist linguists. Rather, these parallels are evidence of a cultural moment in which new ways of thinking about the relationship between the observer and the observed transformed both disciplines. Hayles' discussion finds in both post-Newtonian science and postmodern criticism a move beyond the Cartesian mind-body dichotomy and an acknowledgement of the self-referentiality of language. While the modern novel explores 'the relation between the teller and the tale', contemporary physics explores 'the relation between the observer and the observed system' (41). By positing such parallels, Hayles pushes science toward recognising that language, too, is part of the observed system and hence the insights of literary analysis are relevant to our understanding of how science operates in the world; simultaneously, she pushes literary studies toward a greater engagement with the material ways that science and technology shape conceptions of the world and hence our interactions with it and our selves. …