The long ā is optionally substituted for the final of san before the affix ktic and there is also optional elision of the nasal.,
Thus we have three forms सातिः꣡, सन्तिः꣡ and सतिः꣡ ॥ The word अन्यतरस्याम् 'optionally' has been employed in the sutra for the sake of clearness only; for the विभाषा of 6.4.43 could have been read into it by anuvritti. Lest any one should doubt, that the anuvritti of विभाषा had ceased with the last aphorism, this word अन्यतरस्याम् is employed here.,