Perhaps it’s like this:

aesthetics : canon : art :: rhetoric : grammar : language

Both pictorial art and language are “free creative” acts, that is, each of them forms and shapes its products (images, words) completely separately from the things pointed at. Over time and within a relatively contiguous community of recipients, norms of how these forms should look or sound arise and are endorsed and retained—canons, standards, conventions, grammars, preferred pronunciations, and ultimately the cultural phenomenon of taste.

Consider how often, and how unnoticed, it is that certain constructions are almost entirely conventional, not truly imitative or “representative,” yet they do not arrest our attention. Outlines themselves are an invisible convention; hatch marks for shading are sometimes an invisible convention. In language (I’ll use English, which I’m most familiar with), structural words (prepositions, conjunctions, etc.) tend to remain invisible until, through repetition, odd locution, or misuse, the reader or listener becomes aware of them.

Rules and guidelines eventually develop to describe how images or language work, why certain forms or presentations can appear to be defective and others quite extraordinary. I suspect the rules were developed as teaching aids to instruct the student how to work efficiently and what to avoid, as practical lore and folk wisdom based on previous success or failure. That’s how the warning against splitting infinitives or ending a sentence with a preposition takes root as hard and fast prohibitions. They were introduced as guide for students, who observed the injunctions with deep reverence, but eventually the wise advice became linguistic fetishes enforced with the power of taboo. Curiously, mastery of technical details, and especially prescriptive rules, has become more highly regarded than true expressive excellence: a cursory review of many academic and policy texts will demonstrate that fact.

We are at the 25,000th year of a long history of teaching and refining techniques—and absorbing new modes and practices from elsewhere—about making and using art and language in society, and the guidelines have become very detailed, extensive, and complicated. Knowledge of them has taken on the trappings of esoteric learning, and adepts are honored publicly.

I’ve often run into the situation that a non-artist really likes one of my paintings that I think is poor because of this and that—blemishes or clumsiness or poor technique or other things I can easily see but that the other person just isn’t attuned to. The other person isn’t schooled in the conventions, and thus is less aware of departures from a norm, from those guidelines that form part of the foundations of taste and aesthetics.

When you attend carefully to things in motion or in flux, like spoken language, you’ll observe that at any discrete moment, the image or sound or feeling is indistinct, lacks a precise edge or boundary, is seemingly incomplete. But when it’s taken in the greater flow, in the flux and motion, you easily process and coalesce the whole stream of perceptions and impose an organization so that it seems distinct and precise. Listen to the way people speak: slurred consonants, mushy vowels, missing syllables, warbling pitch, but their utterances seem complete and coherent to you. Likewise, the fuzzy brushmarks in the painting, the brutal chip marks in the stone, the peripatetic vowels in the song.

Words are spoken in long strings of sounds that aggregate and blend together. But because we can move small sections of the sounds around—what we call words—we disaggregate the whole stream. Orthography has followed suit: word spaces were introduced into writing long after entire sentences and thoughts were inscribed on monuments in an unbroken parade of marks. Nowadays, we hear separate words with the reinforcement of having seen the words written as separate entities. (I’m sure you’ve had the experience of not being able to figure out what the song lyric says until you read the words on the album cover. Then you can “hear” the sung words as meaningful, rather than as a muddle of unfathomable sounds.)

Somehow, our attentive faculties enable us to perceive things clearly as they blur by. But when those transient things are made to be static, when the passage is halted, what we perceive undergoes a metamorphosis. Things in flux become like a snapshot of a friend that makes him look odd or funny, because his face is frozen with one eye squinted and the tip of the tongue sticking out of his lips. We don’t see those small details when he speaks, but the photograph records the instantaneous transformations between one stable pose and another. News photographs are particularly susceptible to this kind of freeze-frame exhibitionism. (On opinion and commentary sites, it’s very common to see a photograph of an opponent taken at an unflattering moment and a much more complimentary photograph of a favored person, used for rhetorical effect.)

Sounds, by the way, are harder to stop in a “freeze-frame” manner because we hear them across a span of time. If we halt a sound recording at a specific instant, we will hear a continuous, unvarying tone without any way to construct a full context. In a photograph, despite the interruption to the motion, the full visual field is preserved and we can form a complete context for it.

We construct clarity and precision out of fuzziness every day.