Persistence of One-Dimensional Patterns
When we think of sequences, we envision events in a fixed order in time: first this happens, then that happens, etc. This is true regardless of whether the sequence is descriptive (“I saw this, then I saw that”) or instructive (“Do this, then do that”). The later steps are usually dependent in some way upon completion of the earlier steps. Embryologists observe that the retina develops only after formation of the neural tube. The developmental sequence is fixed: it makes no sense to speak of the retina emerging before the neural tube. Likewise, in baking a pie the crust is made before the pie is placed in the oven; trying to make the crust after baking does not produce good results.3
However, the sequence of floats and marching bands in a parade does not quite fit the model.6 The pattern of the parade sequence persists even when the parade is not moving; it exists independently of time. Unlike the performative steps of a mechanical procedure or the observed stages of a natural process, the sequential ordering of a parade is a one-dimensional pattern of interchangeable elements (bands, floats, drill teams, etc.). Further, if the Navy Band follows the Chamber of Commerce float, in no way does this imply that other arrangements are impossible. It could just as easily be the other way around, with the Navy Band in the lead.
This is how I will use sequence in this book: sequences are persistent, onedimensional patterns composed of interchangeable elements. Many sequential arrangements describe and coordinate activities like baking a pie or building an organism, but it is their persistence, their stability in time, that accounts for their power. A pie recipe is made up of sequences of letters and numbers forming a pattern we call a text. It comprises individual elements drawn from an alphabet, elements that have no inherent meaning in and of themselves but which gain meaning when combined and recombined into one-dimensional patterns.
Before life emerged on Earth there were no sequences, no one-dimensional patterns either to describe what was going on or to guide the behavior of matter. The forces of nature that governed earth, air, fire, and water operated of their own accord. Once sequences appeared, however, strange behaviors emerged that are difficult to explain satisfactorily with the universal laws of nature. If you drop a $20 bill, the laws of physics can tell you that it will fall to the ground, but they cannot tell you that someone else will quickly pick it up.7
To be sure, sequences—whether DNA molecules, ink on a page, or voltages in a chip—are nothing other than ordinary physical objects that obey the laws of nature like everything else. There are no special laws or supernatural activity that somehow exempt sequences from the physical and chemical processes that control the universe. In this sense, sequences are quite ordinary, just more stuff. But in another sense, in their ability to orchestrate the behavior of matter, they are extraordinary.
We must stand ready to look at sequences both ways, as ordinary matter and as something much more. “Central to the notion of a ‘message’ is the difference between the structure of a physical object which follows necessarily from its physical makeup and that which does not,” explains David Hull.8 You and I may readily acknowledge that this book is made of paper, ink, and glue, but unless we are bookbinders by trade, the details of its fabrication are of little interest. The pattern of sequences in the book is what interests us. Sequences lead us to ignore their own physical details and attend instead to their persistent one-dimensional arrangement.