MuU 3.1.9
एषोऽणुरात्मा चेतसा वेदितव्यो यस्मिन् प्राणः पञ्चधा संविवेश । प्राणैश्चित्तं सर्वमोतं प्रजानां यस्मिन् विशुद्धे विभवत्येष आत्मा
eṣo'ṇurātmā cetasā veditavyo yasmin prāṇaḥ pañcadhā saṃviveśa | prāṇaiścittaṃ sarvamotaṃ prajānāṃ yasmin viśuddhe vibhavatyeṣa ātmā
Sanskrit for this text is pending; the English follows the translator's numbering.
That subtle Self is to be known by thought (ketas) there where breath has entered fivefold; for every thought of men is interwoven with the senses, and when thought is purified, then the Self arises.
Translated by F. Max Müller