And where did Wilber get this idea?

Integral Theory: Integral Esotericism - Part Four Alan Kazlev

So instead of body and mind (Descartes' dualism, and its derivatives such as Wilber's exteriors and interiors), there is body, emotional feeling, and thinking. In this way the simplistic Cartesian and post-cartesian (including Teilhardian, Dual-Aspect philosophical, and Wilberian) dichotomy of subject-object or interior-exterior (with mind or consciousness on one side and body on the other) can be replaced by a more phenomenologically appropriate understanding, by which I mean corresponding to individual experience rather than abstractions. In this manner the field of experience the body (which is the physical element of the above mentioned trinity) is part of the field of consciousness (the "I" using the word in the Wilberian sense - upper left quadrant). This is in keeping with the insights of Merleau-Ponty[14].

This Aurobindonian, Neo-theosophical, and Gurdjieffian inspired ontological understanding is very different from Wilber's evolutionary holarchic levels. In the former the mental center or faculty does not include and transcend the physical, the way it does in Wilberian theory. In esoteric ontology, Mind, Emotion/Vital, and Body are all each distinct, and in Sri Aurobindo's Integral Yoga all three have to be equally transformed...

It is not that one is wrong and the other right. Rather there are two complementary positions, the ontological and the evolutionary. It is worth pointing out that most current esotericists also accept and incorporate the evolutionary as well as the ontological perspective. Both the Theosophical and Aurobindonian traditions see evolution as the progressive actualisation of higher ontological faculties, which is exactly what Wilber also teaches (and where did Wilber get this idea in the first place, if not from Theosophy and Sri Aurobindo?). But they also acknowledge these principles as ontological realities in their own right...

Another difference between Wilberian Integral theory and Esoteric Integral theory is that in the latter, represented by Theosophical and Aurobindonian esoteric ontology, and also the Gurdjieffian-Ouspenskian philosophy, the Subjective / "I" perspective is three-fold, representing the three ontological gradations of physical body, emotions or feelings, and thoughts or mind, with an equal degree of ontological distinctiveness between them. In contrast Wilberian theory is still based on the old exoteric dualism of mind and body, or as he prefers to put it, interiors and exteriors.