Yōga Sūtra 4.05

प्रवृत्तिभेदे प्रयोजकं चित्तमेकमनेकेषाम्।

pravr̥ttibhēdē prayōjakaṁ cittamēkamanēkēṣām।

[प्रवृत्ति भेदे प्रयोजकं चित्तम् एकम् अनेकेषाम्।
pravr̥tti = causes of activities; bhēdē = differentiation of; prayōjakaṁ = is useful for; cittam = Chitta; ēkam = is one; anēkēṣām = though manifests as many;]

Differentiation of causes of activities is useful for Chitta, which is one though manifests as many.