Sutra 3.1.4

4. If it be said (that it is not so) on account of scriptural statement as to going to Agni and the rest; we say no, on account of the secondary nature (of the statement).

But the text, 'when the speech of the dead person enters into fire,' etc. (Bṛ. Up. III, 2, 13). declares that when a person dies his organs go into fire, and so on.; they cannot therefore accompany the soul. Hence the text which asserts the latter point must be explained in some other way!—Not so, the Sūtra replies. The text stating that the organs go to fire, and so on, cannot be taken in its literal sense; for it continues,'the hairs of the body enter into herbs, the hair of the head into trees' (which manifestly is not true, in its literal sense). The going of speech, the eye, and so on, must therefore be understood to mean that the different organs approach the divinities (Agni and the rest) who preside over them.