15.16 There are, the Sastras say, 'two kinds of Persons (Purusas)' well known in the world - 'the perishable and the imperishable.' Of the two, the Persons designated by the term 'perishable' (Ksara) are beings conjoint with non-conscient matter of modifiable nature, from Brahma down to a blade of grass,who can be signified also by the term Jivas (individual selves). Here the term Purusa (Person) is used in singular to indicate the common single condition of being conjoined with non-conscient matter. That which is the 'imperishable' (Aksara) is called 'unchanging' (Kutastha), this is the released self, devoid of association with non-conscient matter, remaining in its own form. It is called 'unchangeable' inasmuch as when free from non-conscient matter, It has no specific connection with particular transformations of non-conscient matter like the bodies of Brahma etc. Here also the designation of the term in singular (as expressing a generic class) denoting the totality of liberated selves, is used on account of the single condition of dissociation from non-conscient matter. It does not mean that before this, in time without beginning, there existed but a single liberated self. So it is stated:  'Purified by the austerity of knowledge, many have attained My state' (4.10); and 'They are not born at the time of creation, nor do they suffer at the time of dissolution' (14.2).