अद्वैतं परमार्थो हि द्वैतं तद्भेद उच्यते ।
तेषाम् उभयथा द्वैतं तेनायं न विरुद्ध्यते ॥ १८ ॥advaitaṃ paramārtho hi dvaitaṃ tadbheda ucyate |
teṣām ubhayathā dvaitaṃ tenāyaṃ na viruddhyate || 18 ||18. As non-duality is the ultimate Reality, therefore duality is said to be its effect (Kārya or Bheda). The dualists perceive duality either way (i.e., both in the Absolute and in the phenomena). Therefore the non-dual position does not conflict with the dualist’s position.
Shankara Bhashya (commentary)
How is it that the non-dualist does not conflict with the dualist? The reason is thus stated:—As1 nonduality is the ultimate Reality, therefore duality or multiplicity is only its effect. The Scriptural passages such as, “He is one and without a second”, “He created fire”, etc., support this view. It2 is further borne out by reason as duality is not perceived in the states of swoon, deep sleep or trance (samādhi), in the absence of the activity of the mind. Therefore duality is said to be the effect of non-duality. But the dualists perceive duality alone either3 way, that is, from both the absolute and the relative standpoints. As duality is perceived only by the deluded and non-duality by us who are enlightened,4 therefore our view does not clash with their views. For, the Scripture also says, “Indra (the Supreme Lord) created all these diverse forms through Māyā”, “There exists nothing like duality”. It5 is like the case of a man on a spirited elephant, who knows that none can oppose him, but who yet does not drive his beast upon a lunatic who though standing on the ground, shouts at the former, “I am also on an elephant, drive your beast on me”. Therefore from the standpoint of Reality, the Knower of Brahman is the very self of (even) the dualists. Hence, our, viz., the non-dualistic view does not clash with other views.
It may be asked in view of the differences between the dualistic and the non-dualistic views, how it can be said that the latter does not find any contradiction with the former. The text of the Kārikā gives the reply. It says that the so-called duality does not exist at all. Whatever exists is non-dual Brahman alone. Therefore the non-dualist cannot quarrel with a thing which is ultimately non-existent.
Anandagiri Tika (glossary)
1 As, etc.—We learn from Scriptural evidence that duality is the effect of the non-dual unity. The effect, relatively speaking, is other than the cause, otherwise, one cannot make a distinction between the cause and the effect. Again the Śruti says that all effects consisting of names are mere figures of speech, like the effects of clay, and therefore unreal. The cause, like the clay, alone is real. Therefore effects, being unreal, cannot contradict the cause. Hence non-duality does not clash with duality. Here the word “Bheda,” implying effect is not used in the Sāṃkhya sense of modification.
2 It is, etc.—One perceives duality on account of the activity of the mind. When the mind is at rest, duality is not perceived as in the case of deep sleep, swoon, or Samādhi. Therefore duality is the effect. The non-dualist admits the fact of duality during the state of ignorance. But he denies its reality. Therefore from the standpoint of Reality, non-duality does not contradict duality, as the latter is really non-existent.
3 Either way—That is to say, the dualist holds duality both as the highest Reality and as the relative Reality.
4 Enlightened— It is because our view is supported both by Scripture and reason.
5 It is, etc.—The dualist is self-deluded like the madman who, though standing on the earth, thinks that he is really on an elephant. The person who is driving the elephant does not listen to the foolish cry of the lunatic. Similarly the dualist possessed of a partial view of the truth, thinks of himself as having realised the ultimate Truth, and throws his challenge to the non-dualist, calling upon him to refute his position. But the non-dualist, secure in his position, laughs at this challenge and he bears no ill-will against the dualist as he is the very self of the dualist, his so-called opponent.