In the series ‘The Science of Upaniṣads’, it is Māṇḍūkya (माण्डूक्य) Upaniṣad that we now take up for study and rational review; this is the sixth in the series of eleven Upaniṣads. Māṇḍūkya belongs to Atharva Veda, together with two other Principal Upaniṣads, Muṇḍaka and Praśna. What the word Māṇḍūkya signifies is not definitely known; in the study of the Upaniṣad it is not significant either.
Māṇḍūkya is the smallest of the eleven Principal Upaniṣads under our review; it has only 12 verses, numbered serially from 1 to 12. Nevertheless, it is the tersest of all, expounding in a unique manner the nature of shining of Ātmā in beings, with particular importance to the aspect of CHIT (consciousness). It uncovers four distinct modes of expression of CHIT.
Brevity of the Upaniṣad is an indication of the terseness in contents presentation, warranting detailed study of each verse. However, before moving on to the verses, we may recall our declared adherence to the rational path in the study of Upaniṣads. This may at times entail departure from conventional understanding and teaching by theologians and spiritual luminaries; in such cases the views expressed here may be appreciated with a rational approach befitting this age of scientific spirit. In our study, we shall also pursue our commitment to look for and abide by the consistency of teachings in all the Principal Upaniṣads taken together, which is essential for comprehensive understanding of their philosophy.