Architects can play with every other part of a building. With computers to assist them, and steel to uphold them, as if in clay they can twist, stretch, and hollow walls, roofs, and floors, even merge them; as if on canvas they can lead the eye, or foil it, or trap it. But every good staircase is like every other. The form can be adorned or hidden, or banished either in one-story buildings or by substitution with elevators—but not overcome. There is a limited range of acceptable slopes for a staircase, to which all must conform, or risk injuring their users. Each step must be predictable, and exactly like every other. Stair-climbing is an unconscious, algorithmic act. So is walking, so is typing, so is riding a bicycle; but climbing stairs belongs to a different class—along with driving a car—where error threatens with death. For a joke, you can trip, or fall off a bicycle; but not crash a car, or fall down the stairs. You have time to get to know a new car; but a new set of stairs should not require individual attention.
Consider music. Formality is obvious in classical music. The piece, to be played well, must be considered as something to be reached; and the performer can always fall along the way, by insubordination to the conductor or by infidelity to the composer. Audience members have every right to resent this, however the performer excuses it. Something that mars a performance hits the listener with a jerk—it is the performer who trips up, but the audience who falls. Formality is less obvious, but equally important, in jazz. A sequence of improvisations is not a showcase of individual performers. It is not that every player is an orchestra, but that every player is a conductor. An arrogant classical player is a rebel in a monarchy; an arrogant jazz player, a demagogue in a democracy.
But songwriting is the most formal kind of music. It is because the blues is a rigid form that it can bear the distortions of strong emotion; and indeed, people are never so still as when overwhelmed. If we can, we sit to cry. All popular music has strong, formal structure; which makes it easy to gather with its kin into playlists, and makes it possible for the supply to be kept up. And it is by their formality—by how much alike they are in form—that songs are individualized. Any two pieces of classical music, each with a different structure, sound at first much more alike than any two popular songs, each sharing the same chord structure, rhyme scheme, and instrumentation; just as, although trees are more unlike one another than one person is unlike another, we see the difference between two people more clearly, and find more weight in it, than the difference between two trees.
The danger of too much formality is easy to see. Most of what is worth attaining in life is not repeatable, and is lessened when approached as if it were. Experiences which are had only once do not benefit by formality. Of the rest, some are recurring, but not meaningfully repeatable. They can happen more than once, but are less like climbing stairs than climbing a mountain—which does not, I imagine, improve by being done often. The rest is the repeatable. And repeatable experiences may be no less valuable than singular ones—I would not trade music for youth.
The danger of informality is easy to fall into. Consider poets. Poets are rare for reasons that have nothing to do with poetry (most become songwriters now, who would once have been poets); but those poets that there are, write less than the old poets. This is because of their informality. Free verse is dangerously therapeutic. A good poem in free verse is a unique victory—not the imprint of an emotion, but its draining and defeat. Such poets fail when they approach something that is common to all, and so cannot be exhausted. They cannot make poetry, either of the everyday, or of the ideal.
But think of Petrarch; with the sonnet for his stair he could ascend to and return from the experience of the moment in which he saw (saw so that he therefore loved) his Laura; and as many times as he climbed up to and down from that moment, he never emptied it. Informality always stays on the ground floor; to rise, you must commit yourself to some form capable of bearing you up.