AITAREYA UPANISHAD · 1.1.1

आत्मा वा इदमेक एवाग्र आसीत् । नान्यत्किञ्चन मिषत् । स ईक्षत लोकान्नु सृजा इति ॥ १ ॥

ātmā vā idameka evāgra āsīt । nānyatkiñcana miṣat । sa īkṣata lokānnu sṛjā iti ॥ 1 ॥

In the beginning the Spirit was One and all this (universe) was the Spirit; there was nought else that saw. The Spirit thought, “Lo, I will make me worlds from out my being.”