Meditation

According to the Yoga-Sutra (I.39; II.l1), the initial purpose of meditation is to intercept the flux of ordinary mental activity (vritti), of which he distinguishes five categories: sensory knowledge (pramana), misconception (viparyaya), conceptualization (vikalpa), sleep (nidra), and memory (smriti). Whereas the first two types of mental activity are, by and large, disposed of through the technique of sensory inhibition and concentration, the conceptualizing or imaginative aspect of the mind, as ,well as sleep, are gradually brought under control through the meditative process. The final obstacle to inwardness (pratyak-cetana) is the ever-active memory, which gives rise to thoughts and internal imagery. However, memory is only fully disabled in the highest type of ecstatic realization (i.e., asamprajnata-samadhi). Here the restriction of the subliminal activators (samskara), which are ultimately responsible for the generation of mental activity, is accomplished.

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