Chandogya Upanishad 6.12.2

6.12.2

taṃ hovāca yaṃ vai somyaitam aṇimānaṃ na nibhālayasa etasya vai somyaiṣo 'ṇimna evaṃ mahānyagrodhas tiṣṭhati \
śraddhatsva somyeti \\612.2\

1. ‘Bring hither a fig from there.’ ‘Here it is, Sir.’ ‘Divide it.’ ‘It is divided, Sir.’ ‘What do you see there?’ ‘These rather (iva) fine seeds, Sir.’ ‘Of these, please (aṅga), divide one.’ ‘It is divided, Sir.’ ‘What do you see there?’ ‘Nothing at all, Sir.’ 2. Then he said to him: ‘Verily, my dear, that finest essence which you do not perceive—verily, my dear, from that finest essence this great Nyagrodha (sacred fig) tree thus arises.

3. Believe me, my dear,’ said he, (3) ‘that which is the finest essence—this whole world has that as its soul. That is Reality. That is Ātman (Soul). That art thou, Śvetaketu.’ ‘Do you, Sir, cause me to understand even more.’ ‘So be it, my dear,’ said he.