Trandisciplinarity is both unified and diverse.

• Theoretical: general definition of transdisciplinarity and a well-defined methodology (a methodology corresponds to a great number of methods) (Piaget, Morin)/
• Phenomenological: it implies building models that connect the theoretical principles with the already observed experimental data in order to predict further results. (Gibbons, Nowotny)
• Experimental: it implies performing experiments following a well-defined procedure

There are degrees of disciplinarity which can more or less completely take into account the three methodological postulates of modern science.

Three axioms of methodology of transdisciplinarity:

• ontological_there are different levels of Reality of the Object and the Subject (…) reality is both pragmatic and ontological (…) one has to distinguish the words “Real” and “Reality.” Real designates that which is, while Reality is connected to resistance in our human experience (…) no level of Reality constitutes a privileged place from which one is able to understand all the other levels of Reality (…) Every level is characterized by its incompleteness (…) a finite topological distance could contain an infinite number of levels of Reality. We have work to do till the end of time (…) The Gödelian structure of levels of Reality implies the impossibility of a self-enclosed, complete theory. Knowledge is forever open (…) The zone of non-resistance corresponds to the sacred (…) The unity of levels of Reality and its complementary zone of non-resistance constitutes what we call the transdisciplinary Object, Nicolescu asserts that the different levels of Reality of the Object are accessible to our knowledge thanks to the different levels of Reality of the Subject (…) Our ternary partition (Subject, Object, Hidden Third) is, of course, different from the binary partition (Subject vs. Object) of classical realism.
• logical_the passage from one reality to another is ensured by the logic of the included middle (…) one necessarily discovers contradictions in the theory describing the respective level: one has to assert A and non-A at the same time (…) in the history of science a theory leads to contradictions and one has to invent a new theory solving these contradictions (…) one has to abandon the third axiom of the classical logic [there exists no third term T which i at the same time a and non-A] , imposing the exclusion of the third, the included middle T.
• complexity_the structure of the totality of levels of Reality or perception is a complex structure, every level is what it is because all the levels exist at the same time (…) It is useful to distinguish between the horizontal complexity, which refers to a single level of reality and vertical complexity, which refers to several levels of Reality. It is also important to note that transversal complexity is different from the vertical, transdisciplinary complexity. Transversal complexity refers to crossing different levels of organization at a single level of Reality (…) complexity is a modern form of the very ancient principle of universal interdependence (…) The principle of universal interdependence entails the maximum possible simplicity that the human mind could imagine, the simplicity of the interaction of all levels of reality. This simplicity cannot be captured by mathematical language, but only by symbolic language. The mathematical language addresses exclusively to the analytical mind, while symbolic language addresses to the totality of the human being, with its thoughts, feelings and body (…)

References

Nicolescu, B., 2010. METHODOLOGY OF TRANSDISCIPLINARITY – LEVELS OF REALITY, LOGIC OF THE INCLUDED MIDDLE AND COMPLEXITY. In Transdisciplinary Journal of Engineering & Science Vol: 1, No:1, (December, 2010), pp.19-38

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