hidden conceptual connectors

The least controversial statement possible about the brain's functioning is that it's enigmatic on large scales. Despite knowledge of input and output in any given situation, the complex path in-between can't be interpolated. It's a fuzzy tangle of inherent unpredictability as it continually adapts with each new environmental shift in the flood of external information. Small wonder that some scientists have insisted instead on restricting analysis to the most predictable of tangible, measurable behaviors.

But a statement that contradicts this one is also uncontroversial: from a first-person perspective, the brain's work isn't quite as enigmatic. It yields ephemeral subjective/mental/semantic "sensations" under the catch-all name, the conceptual stream of consciousness. Examination of the stream leads to psychological speculation about its supposed causes, e.g. the dream proves that you have a death-wish. Extraction and conversion of the stream to the form of an ordered chain of logical reasoning is a vital step to publishing polished arguments for others to appreciate and check.

It seems to me that a persistent frailty of these post-hoc explanations of the first-person experience is omission of essential steps. Sometimes it's crystal-clear that something must be missing from the person's fragmentary or abbreviated account. Sometimes the person may not have realized that they skipped a step in the telling; when questioned they say it was too "obvious" to be noticed. Sometimes one or more steps are purposely excised to avert dull boredom of the audience. Hence, although the underlying physical motions in the brain that produced the output are undeniably inscrutable, the perceived conceptual motions in the first-person consciousness or "mind" are also filled with gaps! Pure reason, the foremost ally of philosophers, is reliant on hidden connectors between the manifest thoughts.

• Inventive parts of my brain must be whirring away without my express order or consent. How else can I explain the noteworthy clue that my consciousness can play its own soundtrack in the absence of corresponding sound waves? The first guess is that the music filling the interstices of my attention is randomized firings, but the selection is too often apropos to be due to coincidence. The meaning of the lyrics aligns with my focus. More than a few times, I had an anticipatory song. I read toward the top of the page, heard a song in the "mind's ears", and further down I read a textual header whose content matched up more or less directly to the already-in-progress song (most obviously when the header's a pun on well-known song lyrics). As my eyes searched the page as I read, my brain subliminally picked up the text of the below header in passing and that snippet then seeded a highly meaningful background tune. I mention the "smart jukebox in the head" as a prosaic illustration of the currents which are active yet not consciously initiated.
• The next indication is visual. Abstract topics under extended consideration by me may become entangled in a particular unrelated location from my memories. When I return to the topic, a view (always from the same approximate "orientation") of the associated location "shows up". But unlike the inner jukebox music, the choice of stage has no connection to the topic; it's "just there" as the main sequence of my thought is engrossed in the topic. My theory is that when I'm deeply sunk ("transported") into the topic, my usual contextual awareness of my actual location loses force and allows an arbitrary remembered location to emerge. As I ponder the topic, it intertwines with the secondary setting, and from then on the two are joined. Like the apt background music, this occurrence isn't perceivably helpful to the main process, but it suggests that more is happening than the stream of consciousness (would we call the rest of the activity "brooks"?). 
• By contrast, heuristics can be wonderful aids. A few good mental shortcuts reduce the time and effort to obtain an answer, as long as the error rate is tolerable. What's striking is the frequency at which heuristics develop without deliberation. When a person performs repetitious tasks, generalizations crystallize. If a computer program always asks for confirmation and "Yes" is always clicked in response, there's no need to read the words every time thereafter. Sooner or later users may find it so routine and mindless that they barely can recall the clicking, either. Long exposure and training build an intricate web of heuristic reactions. People who perform identical tasks at their jobs for years appear "dead" to onlookers but they're really more like robots. They do A for case X, B for case Y, C for case Z. Eventually, solely the most exceptional cases manage to evade the heuristics. "In all my years working here, I've never seen..." The ability to leap instantly to the correct course of action isn't as remarkable when the solver is hastily reapplying a hidden, practiced heuristic.
• While sneaky street-smart heuristics receive less credit than forthright book-smart education, the latter depends on unrevealed links too. Verbal learning happens as teachers lay new definitions upon previous definitions. As they become better acquainted with the new ideas, the learners likely won't need to refer to the various mediators that first facilitated their initial understanding. After the information is embedded in the learners, the comparative "glue" employed by the teachers during the lessons is unnecessary. Still, the educated person must acknowledge that these clumsy intermediaries were formerly invaluable for achieving minimal comprehension. The teacher's formula "___ is like a ___" was a bridge that could've been forgotten afterward. Thinking of atoms or other particles as microscopic balls or points is deficient to the reality in several respects, but the image is close enough for an introduction. 
• A skeptic could cast doubt on the necessity of the stepping stones laid during learning. Couldn't the instructor plainly state the base facts rather than fumbling with imperfect comparisons? Perhaps, but ultimately it's unavoidable because all communication is the learning process in miniature. Each word shapes the interpretation of its successors. The importance of context shouldn't be underestimated. When someone proclaims a love for "bouncing", the information intended by the proclamation is unlearnt until the arrival of more details. If according to grammar the object of the bouncing is "pogo stick", then the listener's uncertainty decreases, provided he or she knows about pogo sticks. Similar illumination would happen were the object of the bouncing "rubber ball", "check", "unwelcome guests". The point is that the word "bounce" is isomorphic to multiple stuff, a word like "check" that constrains "bounce" could also be isomorphic to multiple stuff, and the final overall sentence isomorphism is an intersection or conjunction of the possible/candidate isomorphisms for the individual words. It's a fundamentally parallel process that harnesses the ambiguity of isomorphisms to permit efficient and creative messages; word choices need not be exact, and continual recombinations use limited word sets to cover an astronomical range of thoughts real and unreal.
• The sheer power of language for logical reasoning, fused to the uncanny human capacity and motivation for inventing explanations, can give the misleading impression that the form of nonverbal reasoning is no more than unverbalized logic. However, countless counterexamples are everywhere. A familiar category is visual estimation and evaluation such as whether a floor lamp can fit inside a box. Skill at such questions is independent of skill at logical/mathematical questions. Moreover, translating a question into a different format, viz. visualizations, can greatly affect its perceived difficulty. Solutions can arise through subtle analogies. Many anecdotes show a startling similarity in the structure of major breakthroughs: the discoverers were confounded until they adjusted their underlying approach or otherwise became inspired by knowledge from seemingly unrelated domains. In the more mysterious accounts, they arrived at the answer partly by interpreting material from dreams or dream-like meditative states in which frothy free association ended up mentally attaching and attacking the problem in the forefront. Metaphors may be simultaneously ridiculous and indispensable. Asking "what if?" might lead to a fruitless destination. On the other hand, it might lead to the key insight. A nonsensical whole can act as a temporary frame between important contradictions before the thinker determines the plausible interconnection.
• At another level of remove, seasoned experts of a specific mental domain describe ideas about the ideas and assumptions about the assumptions. This "feel" is largely what qualifies the expert as an expert. A novice would pursue tempting and irrelevant side details or surface illusions where an expert would employ the well-honed knack for striking at the most beneficial edge. They speak of a "nose" for the right path or a "sense" for the likeliest "shape" of the right conclusion. For them the domain approximates a familiar environment in which even abstract concepts are almost like manipulable objects. Upon prompting they try to describe the domain's "aesthetics", which probably involve symmetry and complementarity. Their patterns of analysis enable them to quickly decompose a challenge and make it appear easy by a lack of wrong turns. Once again the end result doesn't fully expose the hidden concepts that somehow participated in its birth.
• Lastly, and most mystifying of all, are the opaque reports. "I don't know." No matter how they are pestered, they claim to be oblivious to the origin of their highly-confident outcome. In short they know but not how. Naturally, they could actually be wrong, but for a time at least they express certainty. "It just is." No work is remembered. No argument left memorable traces. It's as if verification is possible but not reverse-engineering. There's no clearer proof for the uninformed nature of our reckoning of our own reckonings.