Jñānaṁ jāgrat ज्ञानं जाग्रत् (sūtrā 8)
Svapno vikalpāḥ स्वप्नो विकल्पाः (sūtrā 9)
Aviveko māyāsauṣuptam अविवेको मायासौषुप्तम् (sūtrā 10)
Jñānaṁ means knowledge. Jāgrat refers to the state of wakefulness or the normal active stage with alert stage of consciousness (8).
Svapna means dream. Vikalpāḥ refers to internal perception. External perception happens through senses and internal perception happens through mind (9).
Viveka means discrimination. A-viveka means absence of discrimination. Māyā means illusion. Sauṣupta means deep sleep. Indiscrimination happens naturally in the deep sleep state or māyā (10).
These three aphorisms are considered together because they refer to the successive stages of mundane level of consciousness. Every person undergoes through these three successive levels of consciousness almost daily. The first stage refers to the normal active stage of awareness, without which no action can take place. Here sensory perceptions play the lead role. Second stage is the stage where one enters the dream state, a prelude to the next stage of deep sleep. Here, mentation plays a significant role, as dreams unfold only through mind. The last of stage of normal consciousness level is deep sleep, where even the mind ceases to function.
During the first stage, the mind responds to the sensory inputs (8th aphorism). Mind is extremely active during this period as it has to act on multitude of sensory stimulations it receives when a person is in active or alert cognitive state. During this state, mind and senses are interdependent. Communication between senses and mind happens in tremendous swiftness. The sensory perceptions leave lasting impressions in the mind known as thoughts that manifest as dreams in the second stage of consciousness, the dream state, as conveyed through 9th aphorism. The third state of consciousness is a sort of delusion, as during the stage of deep sleep one forgets his own inherent nature. Both his senses and mind are completely rested. The 10th aphorism compares this stage to māyā, the deceptive state. It is only due to the veil of māyā, one forgets his inherent nature. It is only māyā that makes a person slide down into fathomless bondage and desire. According Trika philosophy, māyā also is the will of Shiva, which Advaita also endorses. All the three states co-exist at all the time, but only one state is predominant. This is like three types of gunās. All the three gunās prevail at the same time, but only one among them is predominant. This is also the case with five basic elements, ether, air, etc. But there is a significant percept in the tenth aphorism. It says that absence of higher level of consciousness is equivalent to the state of deep sleep. To put it other way, it says that ignorance (avidyā) is nothing but the state of deep sleep, where neither mental activity nor physical activity takes place. What is being discussed in these three aphorisms is only the mundane level of consciousness. There are higher levels of consciousness turya and turyātīta that will be discussed later in this series.
What is discussed above pertains to normal human beings. But, yogis are exceptions. Their level of consciousness is totally different from the consciousness level of ordinary humans. Yogis are those who are able to connect microcosm with macrocosm and remain in that position perpetually. Yogin means yoking. His concentration is always focused. Even in active state (Jāgrat), he remains connected with Shiva, the Ultimate Reality. His sensory perceptions are limited to merely maintain his gross body that merely acts a cover for Shiva within. None of the gross matters is of any interest to him. In the absence of extraneous impressions in his mind, in his dream state also, he remains united with Shiva. His internal perceptions do not undergo any significant changes to cause a dream other than Shiva. His sensory perceptions would have almost lost their intended utilities and therefore do not cause any significant impressions to dream about something else other than his own Shiva. Without any modifications, his consciousness enters the stage of samādi, in his deep sleep state. He enters the state of samādi at his own will and in fact most of the times he remains in the stage of samādi. Samādi is attained by constant practice of cessation of all mental activities, in which the mind retains only the unmanifested impressions. The difference in perceptions happens only if any alternate object is available for consideration. But he does not have an alternate matter to consider. He considers everything as Shiva. He has realised that he is not different from his own Shiva. For him the knowing, the knower and the object of knowing are not different. He has developed unbroken flow of concentration in Shiva. He enters the higher tiers of consciousness turya and turyātīta at his own will and for him the transition from one level of consciousness to another level of consciousness happens with ease. To attain this stage, his free-will would have played a preponderant role.