The Plane of immanence (n.) is a hidden blueprint for things, a hidden structure such as the plan for a tree which is of course necessary for its form but can't be pointed to. It exists on a transcendental dimension, only in a supplementary dimension to that tree to which it gives rise.
The Plane of immanence (n.) is, for example, music, whereby there is a transcendent compositional principle that is not of the nature of sound, that is not 'audible' by itself or for itself.
The Plane of immanence (n.) is, for example, the tree which is given in the seed, but is given as a function of a plan that is not given.
The Plane of immanence (n.) is like a desert, populated by concepts.
The Plane of immanence (n.) contains events, singularities, and concepts.
The Plane of immanence (n.) may be in the mind of a God, or in the unconscious of life, of the soul, or of language. It is always concluded from its own effects. It is always inferred.
The Plane of immanence (n.) is related to concepts in this manner: while concepts are like multiple waves rising and falling, the plane of immanence is the single wave that rolls them up and unrolls them.
The Plane of immanence (n.) is the plane upon which philosophy, not science, works. Philosophy is a matter of infinite speed, whereas science is referential, finite and thus, attempts to 'slow things down'.