योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-81, verse-83

यदि कश्चिद्द्वितीयः स्यात्तदैकस्यैकता भवेत् ।
द्वैतैक्ययोर्मिथः सिद्धिरातपच्छाययोरिव ॥ ८३ ॥

yadi kaściddvitīyaḥ syāttadaikasyaikatā bhavet ,
dvaitaikyayormithaḥ siddhirātapacchāyayoriva 83

83. yadi kaścit dvitīyaḥ syāt tadā ekasya ekatā bhavet
dvaitaikyayoḥ mithaḥ siddhiḥ ātapacchāyayoḥ iva

83. yadi kaścit dvitīyaḥ syāt tadā ekasya ekatā bhavet
dvaitaikyayoḥ mithaḥ siddhiḥ ātapacchāyayoḥ iva

83. If there were any second entity, then the oneness of the one (unity) could be established. The mutual existence of duality and unity is like that of sunlight and shade.

Words meanings summery:

• यदि (yadi) - if, in case that

• कश्चित् (kaścit) - any (second entity) (someone, anyone, some)

• द्वितीयः (dvitīyaḥ) - second, another, a rival

• स्यात् (syāt) - may be, might be, should be

• तदा (tadā) - then, at that time

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

• एकता (ekatā) - oneness, unity, identity

• भवेत् (bhavet) - may be, might exist, should happen

• द्वैतैक्ययोः (dvaitaikyayoḥ) - of duality and unity

• मिथः (mithaḥ) - mutually, reciprocally, together

• सिद्धिः (siddhiḥ) - mutual establishment (establishment, accomplishment, success, proof)

• आतपच्छाययोः (ātapacchāyayoḥ) - of sunlight and shade

• इव (iva) - like, as, as if

Words meanings and morphology

यदि (yadi) - if, in case that

(indeclinable)

कश्चित् (kaścit) - any (second entity) (someone, anyone, some)

(pronoun)

Nominative, masculine, singular of kaścid

kaścid - someone, anyone, some

Derived from 'ka' (who/what) + 'cid' (an emphatic particle)

द्वितीयः (dvitīyaḥ) - second, another, a rival

(adjective)

Nominative, masculine, singular of dvitīya

dvitīya - second, another, a rival

स्यात् (syāt) - may be, might be, should be

(verb)

3rd person , singular, active, optative (vidhi-liṅ) of as

Root: as (class 2)

तदा (tadā) - then, at that time

(indeclinable)

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

(numeral)

एकता (ekatā) - oneness, unity, identity

(noun)

Nominative, feminine, singular of ekatā

ekatā - oneness, unity, identity

Derived from 'eka' (one) with the suffix '-tā'

भवेत् (bhavet) - may be, might exist, should happen

(verb)

3rd person , singular, active, optative (vidhi-liṅ) of bhū

Root: bhū (class 1)

द्वैतैक्ययोः (dvaitaikyayoḥ) - of duality and unity

(noun)

Genitive, neuter, dual of dvaitaikya

dvaitaikya - duality and unity

Compound type : dvandva (dvaita+aikya)

• dvaita – duality, dualism
  noun (neuter)
• aikya – unity, oneness, identity
  noun (neuter)

मिथः (mithaḥ) - mutually, reciprocally, together

(indeclinable)

सिद्धिः (siddhiḥ) - mutual establishment (establishment, accomplishment, success, proof)

(noun)

Nominative, feminine, singular of siddhi

siddhi - accomplishment, success, attainment, proof, establishment

Derived from root 'sidh' (to accomplish, to succeed)

Root: sidh (class 1)

आतपच्छाययोः (ātapacchāyayoḥ) - of sunlight and shade

(noun)

Genitive, feminine, dual of ātapacchāyā

ātapacchāyā - sunlight and shade

Compound type : dvandva (ātapa+chāyā)

• ātapa – sunshine, heat, light
  noun (masculine)
  Derived from 'ā-' (towards) + root 'tap' (to heat, to shine)
  Prefix: ā
  Root: tap (class 1)
• chāyā – shade, shadow, reflection
  noun (feminine)

इव (iva) - like, as, as if

(indeclinable)