Bhagavad-gītā As It Is · Text 18.22
Knowledge, action, determination and happiness in the modes
यत्तु कृत्स्नवदेकस्मिन्कार्ये सक्तमहैतुकम् ।
अतत्त्वार्थवदल्पं च तत्तामसमुदाहृतम् ॥ २२ ॥
yat tu kṛtsna-vad ekasmin
kārye saktam ahaitukam
atattvārtha-vad alpaṁ ca
tat tāmasam udāhṛtam
And that knowledge by which one is attached to one kind of work as the all in all, without knowledge of the truth, and which is very meager, is said to be in the mode of darkness.
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