Chāndogya Upaniṣad 7.22

7.22.1

yadā vai sukhaṃ labhate atha karoti \
nāsukhaṃ labdhvā karoti \
sukham eva labdhvā karoti \
sukhaṃ tv eva vijijñāsitavyam iti \
sukhaṃ bhagavo vijijñāsa iti \\722.1\

1. ‘Verily, when one gets Pleasure for himself, then he is active. Without getting Pleasure one is not active. Only by getting Pleasure is one active. But one must desire to understand Pleasure (*sukha*).’

‘Sir, I desire to understand Pleasure.’