Patanjali Yoga Sutra 4.23
Sanskrit Sutra
तदसंख्येयवासनाभिश्चित्रमपि परार्थं संहत्यकारित्वात्॥२३॥
Swami Vivekananda's translation
The mind, though variegated by innumerable desires, acts for another (the Purusha), because it acts in combination.
Chapter link: Yoga Sutra Chapter 4

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