1 - Top-down and Bottom-up Integration
If we look at each higher as a transcendence (in Spirit) of the previous stage, then - in asymmetrical terms - the lower will be subsumed from the perspective of the higher in a top-down form of integration.
Equally if we look at each higher stage as the making immanent (of Spirit) in the previous stage then - again in asymmetrical terms - the lower will be integrated from the perspective of the higher in a top-down manner.
However when we combine these two aspects of Spirit (transcendence and immanence) as interdependent, then what is forward from one perspective will be backward from the other (and vice versa).
Therefore in dynamic relative terms if transcendence is associated with a top-down form of integration, then immanence will be associated with the bottom-up equivalent.
However if we switch the frame of reference, then immanence will be associated with top-down integration and transcendence with its bottom-up equivalent.
Therefore both the transcendent and immanent directions of development are each associated with top-down and bottom-up integration (with "lower" and "higher" stages having a purely relative meaning).
Now clearly if - as with Wilber - one attempts to look at development unambiguously in terms of just one polar reference frame - defined by the forward direction of transcendence - the approach to integration will be unbalanced (and interpreted in a merely top-down fashion).