Defining "Transdisciplinary"
The word ‘transdisciplinary’ was once associated with the pursuit of a unified theory of everything [see Unity of Knowledge]. Today, transdisciplinarity (especially as practiced by those associated with td-net, a network of scholars funded by the Swiss Academy of Sciences) has come to mean something very close to the definition of interdisciplinarity provided in Defining "Interdisciplinary", plus an emphasis on integrating insights generated outside the academy as well as within it. Transdisciplinarians also stress a case study approach whereas interdisciplinarians tend to tackle more general problems. Interdisciplinarians are generally open to engaging non-academic stakeholders – and indeed have often noted that strategies to integrating across disciplines can also be applied when integrating across any sort of social or cultural division – but have stressed interaction beyond the academy to a much lesser degree. Transdisciplinarians are generally interested in generating knowledge that has both academic and practical implications. Again, interdisciplinarians often do the same, but do not insist on this to the same degree.
In sum, transdisciplinarity has these key elements:
The characteristics identified in Defining "Interdisciplinary"
An emphasis on involving non-academic stakeholders in research
An emphasis on a case study approach [See Wolfgang Krohn, "Interdisciplinary cases and disciplinary knowledge," The Oxford Handbook of Interdisciplinarity (2010), 31-49.
An overview of the transdisciplinary approach is provided in Gertrude Hirsch Hadorn, Christian Pohl, and Gabriele Bammer, "Solving problems through transdisciplinary research," Oxford Handbook of Interdisciplinarity" (2010), 431-52.
While the above definition likely reflects the dominant stream in contemporary transdisciplinary practice, it would not be accepted universally. In the editors introduction to Michael O’Rourke et al, Enhancing Communication and Collaboration in Interdisciplinary Research, Sage, July, 2013, two additional meanings of transdisciplinarity are identified: one involves the formation of a new interdisciplinary field; the other involves transcending disciplines.
Four axioms for transdisciplinarity have been posited by Basarab Nicolescu and associates [Source: "Reframing the conception of nature conservation management by transdisciplinary methodology: From stakeholders to stakesharers" by Gregor Torkara and Sue L.T. McGregor, Journal for Nature Conservation (2012)]:
The ontological axiom is that there are different levels of reality: an internal level of what we think, an external level of things and relationships, and a third level including such items as mathematical formulae. Interdisciplinarians would not object to the idea that an important interdisciplinary task is to draw connections across such levels.
A second transdisciplinary axiom suggests that understanding is to be found in what interdisciplinarians would term ‘common ground’ among what different groups think (and perhaps also what different agents want).
A third axiom suggests that the critical thing for Interdisciplinarians to comprehend is the relationships that exist among the things that we study.
The fourth axiom is more controversial even within the community of transdisciplinarians: that since beliefs are infused with values the transdisciplinarian may often need to essay to change values. We will return to the issue of values below [see Differences in Values]
See also: Basarab Nicolescu, Methodology of Transdisciplinarity, World Futures: The Journal of New Paradigm Research, 70:3-4, 186-99, 2014.
Julie Thompson Klein, Discourses of transdisciplinarity: Looking Back to the Future, Futures 63, 68-74, discusses the implications of three different definitions of transdisciplinarity.
Our colleagues at td-net in Europe discuss defining inter- and trans-disciplinarity.