The Mental-Rational Structure Is Focused on Words

As its name suggests, the mental-rational structure, which Gebser believed began circa 1225 B.C., is characterized by rational, discursive thought, the kind of logical, sequential thinking associated with the left brain.

Whereas the previous structure of consciousness, the mythic, is characterized by “a shaping or designing of images”—a right-brain activity—the mental-rational structure is focused on words.

Gary Lachman
The Secret Teachers of the Western World

Source: The Secret Teachers of the Western World