How a blank surface and repeated sound can change attention
Aryeh Kaplan argued that some ancient mystics used practices resembling sensory deprivation: reducing varied input by gazing at an unmarked surface and repeating a sound. The resemblance matters, but the distinction does too. These practices do not remove all sensation; they narrow what a person attends to.
A visually busy room constantly offers new shapes and details to notice. A blank surface offers few. Repeating a sound likewise gives the mind less novelty to follow. With fewer changes competing for attention, concentration can become more sustained, while ordinary distractions may recede. The resulting experience can feel unusual or absorbed without requiring an external vision or voice.
A disciplined practice, not simply isolation
Sensory deprivation usually suggests an environment engineered to limit incoming signals. Kaplan’s comparison points instead to deliberate techniques: the practitioner keeps attention on a simple stimulus and returns to it when the mind wanders. The repeated sound provides an anchor; the blank field removes visual detail that might pull attention elsewhere.
That framing helps explain why Kaplan connected the methods to mysticism. The point was not merely to sit in a quiet place, but to use repetition and restricted focus as tools for entering a different mode of awareness. His account is an interpretation of ancient practice, not proof that every mystic used the same method or experienced the same effects.
The striking implication is that a practice can alter the feel of consciousness without adding anything dramatic to the room: sometimes the change begins when there is simply less to notice.
