An individual who lives in an oral culture uses his senses differently than one who lives in a literate culture, and with that different sensual deployment comes a different way of conceiving his own relations with his environment, a different conception of his body and a different conception of his self. […] Complete openness to the environment is a condition of optimum awareness and alertness for such a person, and a continual fluent interchange of sensual impression and responses between the environment and himself is the proper condition of his physical and mental life. To close his senses off from the outside world would be counterproductive to life and to thought.

When people begin to learn reading and writing, a different scenario develops. Reading and writing require focusing the mental attention upon a text by means of the visual sense. As an individual reads and writes he gradually learns to close or inhibit the input of his senses, to inhibit or control the responses of his body, so as to train energy and thought upon the written words. He resists the environment outside him by distinguishing and controlling the one inside him. This constitutes at first a laborious and painful effort for the individual, psychologists and sociologists tell us. In making the effort he becomes aware of the interior self as an entity separable from the environment and its input, controllable by his own mental action. The recognition that such controlling action is possible, and perhaps necessary, marks an important stage in ontogenetic as in phylogenetic development, a stage at which the individual personality gathers itself to resist disintegration.

Anne Carson, Eros the Bittersweet