Counterclockwise

The other day I was reading in Astronomy magazine one of my favorite features, “Ask Astro.” There readers pose questions about the universe and astronomy in general, and experts are called in to answer them. This one asked why the Sun orbits our galaxy in a clockwise direction, while the planets orbit the Sun in a counterclockwise direction.¹ And that got me thinking about the arbitrary nature of directions and much else in our daily lives.

After all, the conceptions of “clockwise” and “counterclockwise” didn’t come into use until people started telling time with geared mechanisms instead of the angle of the sun, sand running through an hourglass, bells rung in a church tower, or candles burning down past inscribed markings. Clocks with gears have been invented and reinvented using different driving forces—water, pendulums, springs—in ancient Greece in the 3rd century, China and Arabia in the 10th and 11th centuries, respectively, and Europe in the 14th century. The fact that most round clock faces count time by moving the hands from left to right—clockwise—is based on the usage of early sundials. These instruments track the Sun rising in the east, and therefore casting the shadow from the sundial’s gnomon in the west. Then the Sun moves to the south at midday, casting it’s shadow to the north. And finally, the Sun sets in the west, casting the shadow in the east. All of this, of course, is predicated upon the person observing the sundial facing north as a preferred direction. This daily rotation from west, or left, to east, or right, was so familiar that early clockmakers copied this movement.

Of course, all of these cultures that used sundials and invented mechanical clocks were spawned north of the equator and only lately spread them to cultures and European colonies established south of the equator in southern Africa, South America, and Australia. If those areas had been the home of a scientific, technically innovative, colonizing, and marauding culture, and if the peoples of the Eurasian continent had been inveterate stay-at-homes, then things would have been different.

Clockmakers originating in South Africa, Tierra del Fuego, or Australia might have faced in their preferred direction—south, toward the stormy seas and distant ice flows of Antarctica. And then they would have erected their sundials and drawn their clock faces based on the Sun rising at their left hands and casting a shadow to the west, moving to the north behind them and putting the shadow in front of their faces to the south, and finally setting at their right hands in the west and casting a shadow to the east. Their clock hands would have run in the direction we call “counterclockwise,” and the rest of the world would have followed suit. It all depends on your point of view, which is based on accidents of geography, demography, and historic migrations.

What else might have been different based on these historic accidents?

Certainly, our book texts and traffic signs reflect differing points of view. We in the European-based and -influenced world read texts from left to right, pretty much the same as the movement of our clock hands. But this was not universal. If we had kept the alphabets and scripts of the ancient Hebrews and Arabs, writing from right to left, and orienting their books from what we would consider the back cover to the front, then our literary world would be different and we would stack our library shelves in a different order. But we don’t, because we follow the Latin practice of the Roman culture that dominated the western, and eventually the eastern, end of the Mediterranean Sea and surrounding lands.

The earliest writing forms were different yet again. The Egyptians wrote in both rows and columns, depending on whichever was more convenient, and indicated the direction in which the symbols were to be read by the way that the animal signs—birds, snakes, and so on—faced at the top or side of the text. And anyway, hieroglyphs were for the priestly and aristocratic classes, intended to preserve the thoughts of important people for their future generations, and not for just anyone to read and understand. Early cuneiform writing from Mesopotamia was written from top to bottom and right to left, although they changed that direction from left to right at a later date. Chinese, Japanese, and other Asian scripts are generally flexible, written left to right when in horizontal rows, or top to bottom in columns and then mostly reading those columns from right to left—although sometimes also left to right.

Ancient Greek was the most practical of all, because texts were written and read from left to right for the first line, right to left for the second, back to left to right for the third, and so on. This was economical because they had no fraction of a second lag in brain time between the eyes finishing one row of letters on the right end and then tracking back to the left side of the page to start anew. This form of writing was called “boustrophedon,” or literally “as the ox plows.” Like most things Greek, it was eminently sensible—but it never caught on elsewhere.

And then, as to the shape of our books themselves, consider that what we think of as a “book” is really an invention of medieval monks with their manuscript codices,² followed by Gutenberg and his printing press in Europe of the 15th century. Because Gutenberg was printing single broad sheets, folding them into pages, stacking them, and sewing the stacks together in a continuous, linear format, we have the modern book. Gutenberg probably inherited the idea of printing itself from Chinese books of pasted pages that were developed in the Song Dynasty around the 11th century.³

Before that, the Romans, Greeks, Hebrews, and just about everyone else wrote on scrolls. These were rolled up and packed into cubbies on library shelves, identified for the searcher by clay or wax tags attached to the tube ends. I have often thought that the order of the books we read in the Old and New Testament is rather arbitrary—except for Genesis, of course—and originally was based on whatever scroll you happened to pick up next. Someone must have written out a “cheat sheet” somewhere to direct you to some kind of chronological order after Genesis and throughout the New Testament. But things became easier when the pages were put in neatly linear order in a single sewn book.

A lot of the world we inhabit today—from clock faces, to the way we write, to which side of the road we drive on, to the shape of our keyboards—is pretty much a matter of geography, demography, and perspective. And the solutions we live with are not always the most convenient and sensible.

1. Short answer: The planets formed out of a cloud of dust and gas that started to spin in a particular direction—counterclockwise, when viewed from “above,” or from the Sun’s “north pole”—as it collapsed. But that gas cloud was already moving in another particular direction—clockwise, when viewed from “above” or “north” of the galactic plane. The opposite motions are more or less separate, arbitrary, and related to your point of view.

2. Codices (plural of codex) were handwritten single pages that were grouped together and bound between two wooden boards, as opposed to the rolled scrolls used in earlier times.

3. Printing was presumably invented by the Chinese about four hundred years earlier, where the entire page was carved from a single block of wood. Of course, this was just an advanced form of the rolling seals and stamps that had been in use for thousands of years. Carving a single page made sense when individual Chinese ideograms numbered about 50,000—too many to sort and select as single pieces of type. However, by the Song Dynasty the Chinese printers were doing just that. Gutenberg, with only twenty-six characters to choose from, plus capitals and punctuation marks, had an easier time with movable type.