प्रजापतिर्वा एषोऽग्रेऽतिष्ठत्स नारमतैकः स आत्मनमभिध्यायद्बव्हीः प्रजा असृजत्त अस्यैवात्मप्रबुद्धा अप्राणा स्थाणुरिव तिष्ठमाना अपश्यत्स नारमत सोऽमन्यतैतासं प्रतिबोधनायाभ्यन्तरं प्राविशानीत्यथ स वायुमिवात्मानं कृत्वाभ्यन्तरं प्राविशत्स एको नाविशत्स पञ्चधात्मानं प्रविभज्योच्यते यः प्राणोऽपानः समान उदानो व्यान इति ॥२.६ ॥
In plain words
In the beginning Prajāpati stood alone. Being alone he had no delight. Meditating upon himself, he brought forth many creatures. He saw that they were as though without understanding and without breath, standing like a post; and he had no delight. He thought, "Let me enter within them to awaken them." Making himself like the wind, he entered within. Being one, he could not do it; so he divided himself fivefold, and is called the out-breath, the down-breath, the even breath, the up-breath and the diffused breath.