We can look at a page, a screen or a wall. Writing was the earliest information technology. Screens are on TV's or computers although these are becoming interchangeable.
When we face a wall with eyes open in Zen meditation, we attend not to textual, visual or audiovisual products of mental labour but to the mental states and processes of a psychophysical organism which is a natural sensitive recording device. This is inner subjective, not outer objective, knowledge.
The wall is like a blank page or screen. Thus, attention is focused not on externally generated information but on internally generated responses. It is appropriate to look both without and within, like heeding the mirrors and understanding motor mechanics while driving a car.
The characters in the Chinese Buddhist fantasy novel Monkey are told that the true scriptures are written on blank sheets and Zen Buddhists talk about a direct transmission of truth outside the scriptures.