The shapes of letters in all languages are derived from common forms in nature, according to a new hypothesis.
The idea, in some ways seemingly obvious and innately human, arose however from a study of how robots see the world.
Robots employ object recognition technology to navigate a room by recognizing contours. A corner is seen as a "Y," for example, and a wall is recognized by the L-shape it makes where it meets the floor.
"It struck me that these junctions are typically named with letters, such as 'L,' 'T,' 'Y,' 'K,' and 'X,' and that it may not be a coincidence that the shapes of these letters look like the things they really are in nature," said Mark Changizi, a theoretical neurobiologist at the California Institute of Technology.
Changizi and his colleagues think letters and symbols in Chinese, Latin, Persian, and all 97 of the other writing systems that have been used through the ages have shapes that humans are good at seeing.
"Evolution has shaped our visual system to be good at seeing the structures we commonly encounter in nature, and culture has apparently selected our writing systems and visual signs to have these same shapes," Changizi said.
The idea is put forth in The American Naturalist magazine.
Changizi notes that a basic shape such as "L" can be easily bent to form a "V." He found 36 shapes that require just two or three contours, and he then correlated these shapes to common scenes in nature and in ancient architecture.
"So the figures we use in symbolic systems and writing systems seem to be selected because they are easy to see rather than easy to write," he concludes. "They're for the eye."
Even graphic art that is not necessarily alphabet-based conforms to the idea.
"Company logos, for example, are meant to be recognized, and we found that logos have a high correlation," Changizi said. "Shorthand systems, which are meant to give a note-taker speed at the expense of a commonly recognizable system of symbols, do not."