https://www.wisdomlib.org/hinduism/book ... 39352.htmlcittaṃ vāva saṃ kalpādbhūyo yadā vai cetayate'tha saṃkalpayate'tha manasyatyatha vācamīrayati tāmu nāmnīrayati nāmni mantrā ekaṃ bhavanti mantreṣu karmāṇi || 7.5.1 ||
1. Intelligence is certainly superior to will-power. A person first comprehends, and then he wills. Next he thinks it over again and again, and then he directs the organ of speech. Finally he makes the organ of speech utter the name. All the mantras then merge in the names, and all the actions merge in the mantras.
Word-for-word explanation:
Cittam vāva saṅkalpāt bhūyaḥ, intelligence is certainly higher than saṅkalpa [will-power]; yadā vai cetayate, when one comprehends; atha saṅkalpayate, then one wills; atha, then; manasyati, he thinks; atha, then; vācam īrayati, he directs the organ of speech; tām u nāmni īrayati, he makes speech utter the name; nāmni, in the names; mantrāḥ, all the mantras; ekam bhavanti, are united; mantreṣu karmāṇi, the actions [are united] in the mantras.
Do you think MN 18 has in mind the Chāndogyopaniṣad?
https://suttacentral.net/mn18/en/sujato ... ript=latinEye consciousness arises dependent on the eye and sights. The meeting of the three is contact. Contact is a condition for feeling. What you feel, you perceive. What you perceive, you think about. What you think about, you proliferate. What you proliferate about is the source from which a person is beset by concepts of identity that emerge from the proliferation of perceptions. This occurs with respect to sights known by the eye in the past, future, and present.