Good and pleasant in Hindu philosophy is known as shreyas and preyas. Shreyas and preyas have also been interpreted as ‘preferable’ and ‘pleasurable’. One is ‘electable’ and the other is ‘delectable’. The elucidation of the two terms comes in Katha Upanishad in the context of the dialogue between Yama, the God of death, and Nachiketa (son of Sage Vajashravas), who wants to know what happens to the soul or self after death.
Yama is first evasive, as ‘even the gods entertained doubts about this in days of yore’ (Katha Upanishad I.i.21). The boy, however, persists and Yama relents. As a prelude to his answer, Yama refers to the two ways of life open to man – the spiritual, which is eternal, and the material, which is ephemeral.
Dhirah (spiritually inclined) prefers sreyo marga (supreme goal), the path of shreyas, and freedom from the chain of birth and death.
Mandah (not spiritually inclined person who lacks discrimination) goes for preyo marga (delectable), the path of preyas. He pursues wealth and seeks the means to protect it. He is concerned with securing what he doesn’t have (yoga) and protecting what he has secured (kshema). Death comes to him who constantly thinks that there is only this world (I.ii.6).
He who aspires for the world of the Self becomes immortal. One who is mandah wallows in avidya (ignorance), the other revels in vidya (knowledge). Mudah (non-discriminating people) go round and round like the blind led by the blind (I.ii.5).
The pursuit of shreyo marga involves a firm belief in the theory of karma and rebirth, a strong sense of detachment, taking a guru ‘established in a state of non-difference’ (who sees no duality between self and Self, atman and Paramatma), observing religious austerities without any sense of attachment in preparation for spiritual self-realization, and believing in scriptural guidance for reaching the ultimate goal. It is the attitude of renunciation of the seeker and orientation towards parama purushartha (supreme goal) that counts for the practice of shreyo marga.
Adi Shankaracharya, in his commentary on Katha Upanishad, refers to the two paths, Shreyas and Preyas as nivritti and pravritti. The unwise select the path of pravritti, of worldly activity.