Katha Upanishad Verse 1.3.4
In the chariot analogy, the senses are likened to horses traveling over the roads of sense-objects. The combination of the Atman, senses, and mind is what the wise call the “enjoyer” or the experiencing individual.
Sanskrit Verse
इन्द्रियाणि हयानाहुर्विषयाँ स्तेषु गोचरान् ।
आत्मेन्द्रियमनोयुक्तं भोक्तेत्याहुर्मनीषिणः ॥ ४ ॥
Transliteration
indriyāṇi hayānāhurviṣayām̐ steṣu gocarān ।
ātmendriyamanoyuktaṃ bhoktetyāhurmanīṣiṇaḥ ॥ 4 ॥
Translation
The senses, they say, are the horses; the objects which they perceive, the way; the atman, the senses and the mind combined, the intelligent call the enjoyer.

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