Kavyalankarasarasamgraha 7.65

7.65

caivaṃvidhā kāryabhūtatvātkāraṇamantareṇānupapadyamānā tathāvidhavairasyakāri rāhuśiraśchedalakṣaṇaṃ kāraṇaṃ nālaṅkārarūpaṃ, nāpi rasādirūpaṃ, api tu vastumātrarūpaṃ kalpayati /
ato 'tra vastumātrasyaivaṃvidhasya śabdavyāpārāspṛṣṭasya pratīyamānatā, tadviṣayasya ca kāvyadharmasya dhvananābhidhānasya vācyavācakavyāpāraśūnyāvagamanasvabhāvatvātparyāyoktālaṅkārasparś itvaṃ, taduktam----
"paryāyoktaṃ yadanyena"ityādi /

being of such a kind, because it is an effect and is unintelligible without a cause, implies a cause characterized as the decapitation of Rāhu which produces such unpleasantness—[a cause] not of the nature of an ornament, nor of the nature of aesthetic relish and the like, but rather of the nature of a mere fact. / Therefore, here there is the cognizedness of a mere fact of such a kind, untouched by the operation of the word; and since the poetic property known as suggesting that object has the nature of bringing about an understanding devoid of the operation of the expressed sense and the denoter, it touches upon the ornament of periphrasis. So it is said: / “Periphrasis is when by another…” and so forth.