Man exposed to a variety of fields of experiences where he is faced with different sets of stimuli and consequent responses to it is called Life, having found a successful routine in life and even constant successes, he remains unfulfilled or never finds contentment. When he sees the futility of all his ephemeral achievements and the need for constant action to fulfill himself, driving him to a sense of dejection or despondency, is where he is unknowingly initiated into the realm of introspection or spirituality.
The only equipment available for an individual which is consciousness enmeshed within a biological organism is the capacity for mentation. In both Yoga and Vedanta, this antakarana (inner organ) or the inner mechanism have four distinct agencies of operation: the interrogative aspect/objective mind (manas); the faculty of memory and recall (Citta); the faculty of judgment/subjective mind (buddhi) and the sense of individuality (ahamkara).
The instrument of the registry of stimulation and recall of memory is a repository of all the colorations and conditionings that happen to a person during his/her lifetime — called Vasanas, hence all conditional reactions throughout life stem from this faculty (citta). It’s modulation is called vritti. The sense of the present is generated by vritti. The ‘present’ in Sanskrit is called vartamanam. Vartanam is existence, manam is measuring. Vartamanam is the occasion provided for direct perception and evaluation. The individual thus reacts to the stimulation with respect to his mind conditioned by the latent impressions already stored in it from past experiences, thus making each individual unique.
This can also make him incapable of judging the present in its truest form and rather a judgement conditioned by his past and this superimposition or projection of his mind upon the objects perceived may be called confusion. A mind can be called healthy when the objective mind (manas) comes under the direct disciplining of the subjective mind (Buddhi), The discerning intellect should stand upright like a pillar, without being confused by disturbing thoughts, emotions or memories. When a steady state of consciousness is maintained by the intellect, the pull from all side is met equally (sama). That position is called samadhanam or equipoise. When intelligence maintains a continuous neutral position and does not yield to any emotionally tainted memory, the state that is stabilized is called samadhi.
How is such a state achieved? The person who is trying to actualize the realization of the potential envisaged in a certain probability is called sadhaka. The postulation is called sadhanam. The actual performance or the exertion in a methodical way to bring the actual from the potential is sadhana. One sound that is predominant in all these terms is dha. It has a dynamic affinity with the sound dhi, which means ‘the discerning intelligence’ in all experiences of certitude. In the case of the yoga aspirant, the sadhanam being sought is samadhi.
To bring the subjective mind and the objective aspects of the mind together, where the objective mind is well-disciplined to act faithfully as per the guidance of the subjective mind is the Yoga pointed out in the Geeta. This is accomplished only when the vasanas or the conditioning aspect (ego-centric desires) which is the dividing factor is removed. Thereafter this equanimous Yogin becomes skilled in action — without anxiety for the results, his ego-less actions become, as it were, a purgation of already existing conditioning or the Vasanas. The typical word used in the Geeta to indicate this practical implication of Yoga is self-explanatory — Buddhi Yoga, and consistent and faithful application of Buddhi Yoga into one’s life will take an individual into the culmination of all yoga’s — Samadhi.