Nirguna (attributeless) is the nature of the Soul, the 'Self’. Saguna (attributed) is the nature of the mind, which is present in the form of the universe.+

Sage Sankara’s Supreme Brahman (God in truth) is impersonal, Nirguna (without Gunas or attributes), Nirakara (formless), Nirvisesha (without special characteristics), immutable, eternal, and Akarta (non-agent). It is above all needs and desires. It is always the witnessing subject. It can never become an object as it is beyond the reach of the senses. Brahman is non-dual, one without a second. It has no other besides it. It is destitute of difference, either external or internal. Brahman cannot be described because the description implies a distinction. Brahman cannot be distinguished from any other than It. In Brahman, there is no distinction between substance and attribute. Sat-Chit-Ananda constitutes the very essence or Svarupa of Brahman and not just its attributes. The Nirguna Brahman of Sage Sankara is impersonal.

Remember:~

Nirguna (attributeless) is the nature of the Soul, the Self. Saguna (attributed) is the nature of the mind, which is present in the form of the universe.

The Soul is the knower of the Saguna (mind). The Saguna (the universe) is an illusion from the standpoint of the nirguna, which is the true Self.

Thus, the Saguna (mind/world) is a myth from the standpoint of nirguna, which is the invisible Soul, the Self.

The invisible Soul is the Self and eternal identity. The nirguna (Soul) can remain with or without the Saguna (mind), whereas the Saguna (mind) is dependent on the Nirguna (Soul) for its existence

Nirguna and Saguna are classified only in duality. In non-dual reality, there is neither nirguna nor Saguna; everything is one. Therefore, nirguna and Saguna are one, in essence, that is invisible Soul, which is present in the form of consciousness.

The Saguna is the mind because when the mind is present then all the attributes are present, and when the mind is absent then the attributes are absent.

The Samadhi is the natural state of the invisible Soul, the Self. In the natural state, the attributes are non-existent, and in duality (mind), all the attributes are present.

Thus, the duality and non-duality are the nature of the invisible Soul, the Self. The duality and the nonduality are not some theories. The theoretical duality and nonduality have nothing to do with the ultimate truth or Brahman, or God in truth.

The world in which we exist is present in the form of objective awareness. The whole objective awareness is created out of a single stuff. That single stuff is the Soul, which is present in the form of consciousness. The knowledge of the single stuff is Self-knowledge or Brahma Gnana or Atma Gnana.

The dual (waking or dream) and nondual (deep sleep) experiences appear and disappear. The invisible Soul is the witness of the coming and going of the three states.

All three states are made of single stuff. That single stuff is the Soul, which is present in the form of consciousness. Thus, the single stuff alone is real and eternal and the entire three states merely an illusion created out of the single stuff.

The realization of the single stuff, which is the invisible Soul, which is present in the form of consciousness, is Self-realization.

Until ignorance is present, the three states are experienced as reality. Thus, it is very much necessary to realize that there is no second thing that exists, other than the invisible and unborn Soul, which is present in the form of consciousness. : :~Santthosh Kumaar