ARTICLE Specialisation and the Incommensurability Among Scientific Specialties Vincenzo Politi 1 Ó Springer Nature B.V. 2018 Abstract In his mature writings, Kuhn describes the process of specialisation as driven by a form of incommensurability, defined as a conceptual/linguistic barrier which promotes and guar- antees the insularity of specialties. In this paper, we reject the idea that the incommen- surability among scientific specialties is a linguistic barrier. We argue that the problem with Kuhn’s characterisation of the incommensurability among specialties is that he pre- supposes a rather abstract theory of semantic incommensurability, which he then tries to apply to his description of the process of specialisation. By contrast, this paper follows a different strategy: after criticising Kuhn’s view, it takes a further look at how new scientific specialties emerge. As a result, a different way of understanding incommensurability among specialties will be proposed. Keywords Specialisation Á Incommensurability Á Thomas Kuhn Á Scientific discovery 1 Introduction Thomas Kuhn’s incommensurability thesis is usually discussed in relation to scientific revolutions. In his mature writings, however, Kuhn begins to regard incommensurability as playing a role in the process of scientific specialisation. In his view, the incommensura- bility among specialties is a conceptual/linguistic barrier which drives the process of specialisation and promotes the insularity of specialties. Recently, Wray (2011) has re- developed Kuhn’s original insights on specialisation, agreeing with him that the incom- mensurability among specialties is a linguistic barrier which hampers cross-specialty communication. In this paper, we argue that the incommensurability driving specialisation should not be regarded as a conceptual/linguistic barrier. The problem with both Kuhn and Wray is that, in a sense, they put the cart before the horse: first, they develop a semantic/taxonomic theory of incommensurability; then, they apply such a theory to their discussion of spe- cialisation. By contrast, this paper will follow the opposite strategy. We will take a further & Vincenzo Politi vin.politi@gmail.com 1 Instituto de Investigaciones Filoso ´ficas, Circuito Maestro Mario de la Cueva s/n, Ciudad Universitaria, Coyoaca ´n, C.P. 04510, Mexico, D.F., Mexico 123 Journal for General Philosophy of Science https://doi.org/10.1007/s10838-018-9432-1