A short selection from Essay Thirty-two in Darwin, Dogen, and the Extremophile Choice.
Therefore, since the truth seems to be like the proverbial door, which no one can fail to hit, in this respect it must be easy, but the fact that we can have a whole truth and not the particular part we aim at shows the difficulty of it. Perhaps, too, as difficulties are of two kinds, the cause of the present difficulty is not in the facts but in us. For as the eyes of bats are to the blaze of day, so is the reason in our soul to the things which are by nature most evident of all. —Aristotle 
So how might we characterize Epstein’s “verbal and conceptual behaviors we call ‘ideas’” (essay 16) so they might become familiar to us, not as ghosts in the mind, but as the behavioural species of an internal, but material, branching process not unlike that of evolutionary ecology? If (“in operational and practical fact”—McLuhan) our inner, or covert, behaviour (McLuhan’s “medium”) in response to a thing is its whole meaning for us (McLuhan’s “message”), then knowledge is a complex act of the subtle body. This Buddhist term sounds esoteric, I know, but when referring to the objects of silent meditation it explicitly describes the covert reactions, explorations, manipulations, and (mirror neuron) impersonations that we experience as body-attitudes or kinaesthetically sketched ‘images’; thus thinking manifests with clearly tactile connectivity when we become still enough, and open enough, to wordlessly resolve the body’s in-tendings. If thoughts arise effortlessly, we say they’re involuntary; if they are (selectively) rehearsed, then volition is at work.
a six-layer anatomy of behavioural intelligence
1 Except in the heart and the gut, smooth muscle tensions and other autonomic body responses are literally e-motional. Thus emotional affect meanings of objects and events arise involuntarily from prevailing states of body chemistry, and they are associated with direct input from the superficial senses as well as with voluntary motions and tensions of the skeletal muscles. Then, forming five more layers of felt intelligence, ‘motional effects’, whether overt, covert, innate or learned, evolve into whole ‘ecosystems’ of meaning when: 2 postures and programs adapted for direct survival impart reaction meaning to objects and events; 3 the body’s ‘measuring’ of extension, distance, and resistance to movement or deformation imparts exploration meaning to objects and events; 4 the action of moving and rearranging the ‘parts’ previously explored imparts manipulation meaning to objects and events; 5 our mirror neuron reflection, or personification of ‘other selves’, imparts imitation meaning to objects and events; and 6, by transposing all these direct interactions to altogether separate ‘closed behavioural fields’, particularly in the mouth and throat (language: essay 35) but perhaps also in the eyes and face (imagination: essay 43), for meta-level manipulation and composition (thus a covert displacement of meaning-4 objects and events), motor-program-traces are abstracted and associated as mental constructs to articulate formal meaning: we call this “thinking”. [The last three layers are clearly highly developed for, and the last layer—experienced as indirect mediation—is probably unique to, technological intelligence.]
1. Aristotle. 1941 in Richard McKeon, ed., The Basic Works of Aristotle. New York: Random House. (Reprinted translations prepared under the editorship of W.D. Ross.) p. 712 (993b3-993b11 of Bk. II, Metaphysics). Also see Locke, John. 1974 Anchor Books edition, “An Essay Concerning Human Understanding”  in Prof. Richard Tayler abridge. The Empiricists. Garden City NY: Doubleday. pp. 7-133. On p. 20 Locke writes: “The simple ideas we have, are such as experience teaches them us; but if, beyond that, we endeavour by words to make them clearer in the mind, we shall succeed no better than if we went about to clear up the darkness of a blind man’s mind by talking…” Here we see how Aristotle’s acknowledgement that ideas are prior to language continued in Western science.