In his lectures on Raja Yoga, Swami Vivekananda devotes considerable attention to the “chitta”, or basic human consciousness. One of the primary practices of Raja Yoga is the observation and stilling of the waves that arise in the chitta or “mind-stuff” as a result of sense impressions that reach the chitta, and which then lead to reactions in the form of “waves” in that basic mind-stuff. The senses receive impressions from the outer world and deliver them to the mind where they impinge on the chitta and create waves. Those waves develop habitual patterns of both recognition and response, memory and reaction, which then become the foundation for the action of the individual in the world. Most of the action of the chitta is below the level of conscious intention. This brings about habitual patterns of interaction between the individual and his environment.
Sri Aurobindo expands on this analysis: “Chitta, the basic consciousness, is largely subconscient; it has, open and hidden, two kinds of action, one passive or receptive, the other active or reactive and formative. As a passive power it receives all impacts, even those of which the mind is unaware or to which it is inattentive, and it stores them in an immense reserve of passive subconscient memory on which the mind as an active memory can draw. But ordinarily the mind draws only what it had observed and understood at the time,–more easily what it had observed well and understood carefully, less easily what it had observed carelessly or ill understood; at the same time there is a power in consciousness to send up to the active mind for use what that mind had not at all observed or attended to or even consciously experienced.”
“This action of memory is so fundamental to the entire mental action that it is sometimes said, memory is the man. Even in the submental action of the body and life, which is full of this subconscient Chitta, though not under the control of the conscious mind, there is a vital and physical memory. The vital and physical habits are largely formed by this submental memory. For this reason they can be changed to an indefinite extent by a more powerful action of conscious mind and will, when that can be developed and can find means to communicate to the subconscient Chitta the will of the spirit for a new law of vital and physical action. Even, the whole constitution of our life and body may be described as a bundle of habits formed by the past evolution in Nature and held together by the persistent memory of this secret consciousness. For Chitta, the primary stuff of consciousness, is like Prana and body universal in Nature, but is subconscient and mechanical in nature of Matter.”
Sri Aurobindo, The Synthesis of Yoga, Part Four: The Yoga of Self-Perfection, Chapter 5, The Instruments of the Spirit, pp. 620-621