On that point I recall the following from Wilber of long ago saying that to advance to the next level doesn’t require deep horizontal development in a level, just a necessary degree. For example one doesn’t have to be a great athlete or dancer in body awareness to advance to the emotional level, etc. The great athlete is extending his skill horizontally at the same level. And that’s what I think happens in the rational level, that the so-called postformal levels are the horizontal equivalent of the great athlete in the great mind.
Where they do come into play though is in going postmetaphysical. This requires both integrating the so-called states at the rational level and leaving behind the metaphysical interpretation inherent to that level. Note that the post-formal levels above also still retain the metaphysical interpretation as evidenced in the MHC and Wilber’s writings via a false reasoning. A real reasoning though, grounded in embodiment, leaves behind the metaphysical interpretation and transforms the horizontal postformal stages allowing the opening to go trans-rational. But it cannot do that in itself, also requiring methods to transform our so-called states.
The so-called states of subtle and causal are as Wilber intuitied related to dream and deep sleep, being very early human stages of body-mind. It is through self-reflective techniques like meditation that go back down to (involved) and focus on these early brain states that transforms them into subtle and causal levels, so-called tier 3 developments. And all via a functioning rational ego. Or at least when turned back on itself so it can then dive deeper. Hence such meditative practices emerged or co-arose in history at the same time as the rational ego.
While systematic logic or beyond is not required for this process, at least a real embodied reasoning is. And that kind of reasoning is the next actual post-formal level, and one just emerging perhaps in the last century or so. As I said, the MHC levels are really just horizontal extensions of the egoic-rational level with its metaphysical underpinnings. It is ‘false’ not because it is not actual but only in relation to a more embodied and developed ‘real’ reasoning. Recalling Levin, Goddard and Washburn the egoic-rational necessarily entails a temporary dissociation from our earlier development to establish itself. It comes back around though when it looks at itself and begins the return journey of involution to integrate its earlier base body-mind and that, combined with the recognition of a reason based in that embodiment, takes us forward into the next level of non-dual integral-aperspectival.
Now all the above still doesn’t get at the generative mechanisms (machines) of this process. And that’s where the endo-relational structure of image schema might add to this mix as causal agents. The metaphors that arise from them would add to describing that process for the subtle level. All of this has already been explored in various posts and threads, I just need to weave that together here. For example, recall that image schema are compared to the archetype as such by Knox. And that image schema are devoid of content like our very early base awareness (states thread). More to come as connections are made.