Abstract
Ancient Greeks added vowels to a consonantal language and changed their horizontal writing direction from right-to-left to left-to-right. The idea that the dextra] majority in ancient Greece developed left-to-right writing solely because writing efficiency was greater is questioned. Cerebral hemispheric functions that might be involved during fixation pauses in reading suggest that horizontal ancient Greek was read more efficiently from left to right than from right to left, the other direction in which it usually was written. The same considerations suggest that horizontal consonantal scripts are read more efficiently from right to left than from left to right. The importance of boustrophedon, a continuous writing style, in the development of left-to-right writing and aspects of the reciprocity between cerebral hemispheric functioning and writing direction of vocalic scripts are discussed.