According to Advaita Vedanta, the science of Self-Realization (which we call Self-Inquiry), requires a different approach than the sciences involved in discovering the complexities of the Universe. Both approaches are similar in one way in that our consciousness with focused attention and awareness is used as an instrument of perception to gain knowledge.
Sciences involving the exploration of the universe and its laws focus the attention outside to perceived objects (time, space, matter, laws of motion, gravity, mass, etc.) to determine their nature. When attention and awareness are focused on such analysis, the relationships between various objects according to universal laws becomes clear. This is due to the inherent power of consciousness to discover and make known to itself anything that it focuses attention on. That is how sciences (Mathematics, Physics, Medicine, etc.) move forward.
However, the theoretical limit to understanding objective phenomena is always there to the extent that the observed phenomena is based on the very nature of the observer. It is not clear how precisely the relationship between the subject and the object can be determined scientifically. Philosophically, this is due to the logical difficulty of separating the subject from the object and demonstrating their independence.
Science of the Self, however, is a radical departure from the physical sciences and has a different aim. Here attention is directed inwards towards the subject and not outwards towards objects of perception. The classic methodology given by Sri Ramana for Self-Inquiry is to ask oneself with attention and inquire, “Who am I?” This is done in order to introvert the mind and drive it deeper into its source. In Self-Inquiry, the quality of consciousness itself becomes the center of attention. In this method, consciousness is not focused anywhere or on anything other than itself.
Language is not perfect but there are many ways to say this. Attention focused on attention itself is Self-Inquiry. Consciousness becoming self-focused is Self-Inquiry. Mind turning inwards to its source is Self-Inquiry. Awareness aware of itself is Self-Inquiry. All of these are variations of the same process and basically refer to the same thing. These statements indicate that one should quietly abide in one’s own sense of identity and being with full awareness.
This is not an easy notion to grasp. The Self-Inquiry methodology does not present the aspirant with an image or a sound to concentrate on. Because we are so dependent on our sense of hearing and sight even for meditation and prayer, Self-Inquiry presents a challenge. People often find it difficult to know what to focus in doing the Self-Inquiry because they associate their identity and thus consciousness strongly with the body.
This is why Sri Ramana used to say that Self-Inquiry is not for everyone to take on immediately. I have observed this phenomena carefully for a long time. People find meditation, yoga, tantra, chakras, and kundalini methods much more interesting and exciting to talk about and practice than Self-Inquiry. It is because all of these Yoga systems are directly or indirectly based on producing changes in the physical or the subtle bodies which one can experience.
Consumption of experience in some form or another is natural to all living beings. Self-Inquiry points, however, to the subject; the one who experiences. What is the nature of the one who experiences? Self-Inquiry shifts our attention from perception to the perceiver. Who is the one who perceives and experiences reality?
The practice of meditation and yoga leads the mind to temporarily withdraw the senses from objects of perception. However, internal perceptions in meditative states or Samadhi will most likely still exist. These internal perceptions may manifest in a number of ways including that of visions of angels, holy sages, the Goddess. Various spiritual and religious symbols often appear spontaneously in the mental eye of the aspirant during meditation or contemplative prayer and there may also be experiences of lucid dreaming states. So even in higher meditation states, the distinction between the subject and the objects of perception continues as we engage in and consume one experience after another.
Self-Inquiry, on the other hand, is found to be boring and irrelevant by many people because it promises them no special experience to enjoy other than being their own self. People should always do what feels natural. Nothing can be forced.
Eventually with the practice of meditation and other types of yogas, the mind becomes more subtle. The understanding of the nature of consciousness as free from outer perception (of physical objects) as well as internal perceptions (dreams, visions, other mental experiences) can then start to emerge. Once the independent nature of consciousness (free from all perceptions) is understood, one can recognize the essential quality of existence and pure being in the midst of various experiences.
When attention/awareness become self-focused, that is called Self-Inquiry. When attention lights up attention, awareness lights up awareness, consciousness lights up consciousness, Self is Realized as Sat-Chit-Ananda, the ultimate subject, the very core of being. Sri Ramana called it simply the Heart, whose nature is that of silence which is beyond all understanding.