In Samadhi the yogi knows nothing, sees no universe; so if there is nothing but blankness.+

Sage Sankara says ~  VC  56. Neither by Yoga, nor by Sankhya, nor by good work, nor by learning, but by the realization of one's identity with Brahman is Liberation possible, and by no other means. 

Brih Upanishad: page 32. "Yoga does not yield truth or liberation."

One who is in Samadhi will not know that this universe as the consciousness; therefore yoga is not the means to Self- knowledge or Brahma Gnana or Atma Gnana.

 In Samadhi the yogi knows nothing, sees no universe; so if there is nothing but blankness. The blankness is not the Advaitic wisdom.

The yogi does not know the nature of the universe. If the universe is not seen in the Samadhi then there is no need to use the word Atman and Brahman.  The yogi is unaware of the truth, which is beyond form, time, and space. 

By shutting his eyes in Samadhi, the yogi does not know the universe, which confronts him. Hence, the universe can't be known as the Soul or the consciousness through yoga.

One is in a non-dual condition in deep sleep or Samadhi, One without a second, true, but he did not know it at the time. He says only in the waking experience afterward. Hence, there must be an inquiry so that you find non-duality whilst you are awake so that you can see nonduality at the time not afterward. Hence, too the need for inquiring into the nature of the universe and knowing it as the Soul or the consciousness whilst one is awake, and not during sleep or Samadhi.

Advaitic truth is the ultimate truth.  Yogis, mystics, and religious teachers do not accept the path of wisdom because it pries into the truth, the source, and the validity of the knowledge they claim. Therefore, it is the most difficult part of the study of Advaita.

That is why Sage Sankara said:~VC-63- Without causing the objective universe to vanish and without knowing the truth of the Self, how is one to achieve Liberation. 

The universe in which we exist will not remain as reality when wisdom dawns. The universe is a mere mirage created out of consciousness and there is the conscious awareness of unity in diversity because there is no second thing that exists other than consciousness.

Lord Krishna confesses that the oldest wisdom of India (Advaitic wisdom) has been lost: people misinterpret and falsify it today as they did then. It is not yoga but the philosophic truth. But nobody knows it. The teachers of philosophy and leaders of mysticism or religion do not want to inquire into the truth and have no time for it. (Gita –Chap- IV-v.2)

In Gita Chap.IV where Lord Krishna says:~ "This yoga has been lost for ages" the word yoga refers to Gnana yoga, not other yogas: the force of the word this is to point this out.

Lord Krishna describes some of the other yogas but devotes this chapter separately to Gnana Yoga. So one sees even in those ancient days people did not care for Advaita; they wanted religion; hence Gnana got lost. That is why Krishna calls it "the supreme secret." Krishna points out that yoga must-see "Brahman in action."

Neither Yogic Samadhi nor bliss nor worldly pleasure should be allowed to draw one away from evenness; for neither can give the ultimate truth or Brahman. When one is distracted by either, either internal or external bliss, it should by effort be drawn back to steadiness, evenness. This state alone yields the ultimate truth or Brahman.  Intellectually knowing the truth is only an imagination, whereas realizing the truth knows it as such.

Yogis assume that thoughtlessness is wisdom. And the Samadhi is the bliss. Bliss is the ultimate experience.

Yogic theories are based on the false self (you) within the dualistic illusion (waking). The ‘Self is not the ‘I’,  but the ‘Self’ is the Soul, which is present in the form of consciousness.   

If the ‘Self’ is not ‘I’  but the formless, timeless and spaceless  Soul, then whatever is experienced on the base of ‘I’ is bound to be a hallucination within the dualistic illusion.

The yogic Samadhi is a reality within the domain of form, time,  and space, but from the standpoint of the Soul, the innermost self, yogic Samadhi is merely an illusion.

The yogi cannot keep out a portion of the consciousness.  It is utterly impossible. It thoughtlessness is not Self-realization.   The thoughts come to the thinker within the illusory dualistic world.   

The thoughts, thinker, and the world in which the thinker exists are created out of single stuff. That single stuff is the Soul, which is present in the form of consciousness. Knowledge of the single stuff is Self-knowledge or Brahma Gnana or Atma Gnana.

Self-knowledge or Brahma Gnana or Atma Gnana is the only tool to get rid of ignorance.  Without getting rid of ignorance,  Self-realization is impossible.  Self-realization is possible only through Self-knowledge or Brahma Gnana or Atma Gnana.

That is why Sage Sri Sankara, indicated in Bhaja Govindam says: ~ (Jnana Viheena Sarva Mathena Bajathi na Muktim janma Shatena) ~ One without knowledge does not obtain liberation even in a hundred births, no matter which religious faith he follows.

Yogic Samadhi is an egocentric practice based on the false self within the dualistic world, which is an illusion created out of consciousness.

Buddha gave up yoga after practicing it for six years. He saw it could not yield truth.

Buddha gave up his austerities of yoga as impossible and useless. Thus,  Buddha got enlightenment only after he gave up Yoga. (Page.70/71 "Buddhism In Translation” by Warren)

Unless one exercise his Buddhi--reason--there is no chance of getting the ultimate truth or Brahman or God in truth.

Buddhism has not proved the truth of Nonduality. Bhagavan Buddha pointed out the unreality of the world, we agree. He told people they were foolish to cling to it. But he stopped there. He came nearest to Vedanta in speech but not to Vedanta fully.

Only when we independently search for the truth without religion and its doctrine then we will be able to realize the truth beyond form, time,  and space. :~Santthosh Kumaar