Katha Upanishad 3.4

यस्तु विज्ञानवान्भवति युक्तेन मनसा सदा | तस्येन्द्रियाणि वश्यानि सदश्वा इव सारथेः ॥

yas tu vijnanavan bhavati yuktena manasa sada | tasyendriyani vashyani sadashva iva saratheh ||

But he who has understanding, whose mind is always controlled — his senses are manageable, like the good horses of a charioteer.

किन्तु जो विज्ञानी है, जिसका मन सदा युक्त (संयत) रहता है — उसकी इन्द्रियाँ सारथी के सद्-घोड़ों की भाँति वश्य हो जाती हैं।