योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-42, verse-50

विज्ञास्यत्यकृतार्थत्वं क्षणान्तरकदर्थनैः ।
उपायं कल्पनात्मानमनुपायं विदुर्बुधाः ॥ ५० ॥

vijñāsyatyakṛtārthatvaṃ kṣaṇāntarakadarthanaiḥ ,
upāyaṃ kalpanātmānamanupāyaṃ vidurbudhāḥ 50

50. vijñāsyati akṛtārthatvam kṣaṇāntarakadarthanaiḥ
upāyam kalpanātmanam anupāyam viduḥ budhāḥ

50. kṣaṇāntarakadarthanaiḥ akṛtārthatvam (saḥ) vijñāsyati
budhāḥ kalpanātmanam upāyam anupāyam viduḥ

50. One will realize one's state of unfulfillment through the torments of future moments. The wise (budhāḥ) know that any means (upāya) whose nature is imagination (kalpanātman) is not a true means (anupāya) at all.

Words meanings summery:

• विज्ञास्यति (vijñāsyati) - he/she/it will know/understand/realize

• अकृतार्थत्वम् (akṛtārthatvam) - the state of being unfulfilled, unfulfillment

• क्षणान्तरकदर्थनैः (kṣaṇāntarakadarthanaiḥ) - by the torments of other/future moments

• उपायम् (upāyam) - means, method, expedient

• कल्पनात्मनम् (kalpanātmanam) - whose nature is imagination, having imagination as its self

• अनुपायम् (anupāyam) - not a means, no means

• विदुः (viduḥ) - they know, they understand

• बुधाः (budhāḥ) - the wise, intelligent ones

Words meanings and morphology

विज्ञास्यति (vijñāsyati) - he/she/it will know/understand/realize

(verb)

3rd person , singular, active, future indicative (lṛṭ) of vijñā

Prefix: vi

Root: jñā (class 9)

अकृतार्थत्वम् (akṛtārthatvam) - the state of being unfulfilled, unfulfillment

(noun)

Accusative, neuter, singular of akṛtārthatva

akṛtārthatva - the state of not having achieved one's object, unfulfillment

Compound type : nañ-tatpuruṣa (a+kṛtārthatva)

• a – not, non-, un-
  indeclinable (prefix)
• kṛtārthatva – the state of having achieved one's object, fulfillment
  noun (neuter)

क्षणान्तरकदर्थनैः (kṣaṇāntarakadarthanaiḥ) - by the torments of other/future moments

(noun)

Instrumental, neuter, plural of kṣaṇāntarakadarthana

kṣaṇāntarakadarthana - torment of another moment, affliction of subsequent moments

Compound type : ṣaṣṭhī-tatpuruṣa (kṣaṇāntara+kadarthana)

• kṣaṇāntara – another moment, a subsequent moment
  noun (neuter)
• kadarthana – torment, abuse, degradation
  noun (neuter)
  Prefix: kad
  Root: arth

उपायम् (upāyam) - means, method, expedient

(noun)

Accusative, masculine, singular of upāya

upāya - means, method, approach, remedy, expedient

Prefix: upa

Root: i (class 2)

कल्पनात्मनम् (kalpanātmanam) - whose nature is imagination, having imagination as its self

(adjective)

Accusative, masculine, singular of kalpanātman

kalpanātman - whose self or nature is imagination, unreal, illusory

Compound type : bahuvrīhi (kalpanā+ātman)

• kalpanā – imagination, conception, fiction
  noun (feminine)
  Root: kḷp (class 1)
• ātman – self, soul, essence, the supreme (ātman)
  noun (masculine)

अनुपायम् (anupāyam) - not a means, no means

(noun)

Accusative, masculine, singular of anupāya

anupāya - without means, no means, a bad means

Compound type : nañ-tatpuruṣa (an+upāya)

• an – not, non-, un-
  indeclinable (prefix)
• upāya – means, method, approach
  noun (masculine)
  Prefix: upa
  Root: i (class 2)

विदुः (viduḥ) - they know, they understand

(verb)

3rd person , plural, active, present indicative (laṭ) of vid

Root: vid (class 2)

बुधाः (budhāḥ) - the wise, intelligent ones

(noun)

Nominative, masculine, plural of budha

budha - wise, intelligent, learned

Root: budh (class 1)