Not only the classicist, but even the layman with a casual interest in Greek philosophy is familiar with the allegory which Plato employs in the Phaedrus to describe the nature of the soul in terms, as he says, that are ‘within human power’:

Both classical scholars and cultivated laymen alike, on the other hand, have seldom been aware of a strikingly similar allegory occurring in one of the most celebrated works of the final period of Vedic literature, the Kaṭha Upaniṣad:

For their part, indologists have taken due notice of the puzzling similarity from early on, albeit with differing assessments. Already a century ago, in connection with the Kaṭha passage, Keith observed that ‘the contrast with the Platonic metaphor of the Phaidros is as obvious as the parallel’, further on passing his judgement that in spite of the interesting parallelism ‘the details of the two [metaphors] are perfectly distinct, for Plato uses the conception to illustrate the struggle between the rational and the irrational elements in the soul, and his distinction of θύμος and ἐπιθυμία has no real parallel in the Upaniṣads’. On the other hand, Belvalkar and Ranade evidently did not share his caution, as they enthusiastically aver that ‘the extraordinary resemblance of the two descriptions down to the smallest details staggers us, and we must confess we do not know how to account for it’. Almost in between there is Radhakrishnan's opinion that ‘in spite of difference in details, the Kaṭha and Plato agree in looking upon intelligence as the ruling power of the soul … and aiming at the integration of the different elements of human nature’.