योगवासिष्ठः yogavāsiṣṭhaḥ - book-6, chapter-33, verse-30

द्वित्वसंकल्पतो द्वित्वमेकस्यैव प्रवर्तते ।
अद्वित्वसंविदा द्वित्वमनेकस्यापि नश्यति ॥ ३० ॥

dvitvasaṃkalpato dvitvamekasyaiva pravartate ,
advitvasaṃvidā dvitvamanekasyāpi naśyati 30

30. dvitvasaṃkalpataḥ dvitvam ekasya eva pravartate
advitvasaṃvidā dvitvam anekasya api naśyati

30. ekasya eva dvitvasaṃkalpataḥ dvitvam pravartate
advitvasaṃvidā anekasya api dvitvam naśyati

30. Duality (dvitva) manifests for a singular entity through its resolve (saṃkalpa) for duality. Conversely, by the understanding of non-duality, duality is destroyed even for multiple entities.

Words meanings summery:

• द्वित्वसंकल्पतः (dvitvasaṁkalpataḥ) - from the resolve of duality, by the intention of duality

• द्वित्वम् (dvitvam) - duality, twoness

• एकस्य (ekasya) - of the one, of a single (entity)

• एव (eva) - only, indeed, precisely

• प्रवर्तते (pravartate) - arises, manifests, proceeds, occurs

• अद्वित्वसंविदा (advitvasaṁvidā) - by the self-awareness of non-duality, by the understanding of non-duality

• द्वित्वम् (dvitvam) - duality, twoness

• अनेकस्य (anekasya) - of the many, of the manifold

• अपि (api) - also, even

• नश्यति (naśyati) - is destroyed, perishes, vanishes

Words meanings and morphology

द्वित्वसंकल्पतः (dvitvasaṁkalpataḥ) - from the resolve of duality, by the intention of duality

(indeclinable)

Compound type : tatpurusha (dvitva+saṃkalpa)

• dvitva – duality, twoness, being two
  noun (neuter)
• saṃkalpa – intention, resolve, will, imagination, mental concept (saṃkalpa)
  noun (masculine)
  Prefix: sam
  Root: kḷp (class 1)

Note: -tas suffix creates an ablative sense or indeclinable.

द्वित्वम् (dvitvam) - duality, twoness

(noun)

Nominative, neuter, singular of dvitva

dvitva - duality, twoness, being two

एकस्य (ekasya) - of the one, of a single (entity)

(pronoun)

Genitive, masculine, singular of eka

eka - one, single, unique

एव (eva) - only, indeed, precisely

(indeclinable)

प्रवर्तते (pravartate) - arises, manifests, proceeds, occurs

(verb)

3rd person , singular, middle, present (laṭ) of pravart

Prefix: pra

Root: vṛt (class 1)

अद्वित्वसंविदा (advitvasaṁvidā) - by the self-awareness of non-duality, by the understanding of non-duality

(noun)

Instrumental, feminine, singular of advitvasaṃvid

advitvasaṁvid - self-awareness or direct perception of non-duality

Compound type : tatpurusha (aditva+saṃvid)

• aditva – non-duality, oneness
  noun (neuter)
• saṃvid – knowledge, awareness, consciousness, direct perception
  noun (feminine)
  Prefix: sam
  Root: vid (class 2)

द्वित्वम् (dvitvam) - duality, twoness

(noun)

Nominative, neuter, singular of dvitva

dvitva - duality, twoness, being two

अनेकस्य (anekasya) - of the many, of the manifold

(pronoun)

Genitive, masculine, singular of aneka

aneka - not one, many, manifold, various

Compound type : nañ-tatpuruṣa (a+eka)

• a – not, non-
  indeclinable
• eka – one, single
  pronoun (masculine)

अपि (api) - also, even

(indeclinable)

नश्यति (naśyati) - is destroyed, perishes, vanishes

(verb)

3rd person , singular, active, present (laṭ) of naś

Root: naś (class 4)