As the relation between the perceiving capacity and the object of perception is a constant one so also is the relation between the sphoṭa and the nāda as the manifested and the manifestor (_Vākyapadīya_ 98). Just as the image varies corresponding to the variation of the reflector, as oil, water, etc., so also the reflected or manifested image differs according to the difference of the manifestor (_Vāk._ 100). Though the manifestation of letters, propositions and names occurs at one and the same time yet there seems to be a “before and after” according to the “before and after” of the nāda utterances (_Vāk._ 102). That which is produced through the union and disunion (of nādas or dhvanis) is called sphoṭa, whereas other sound-perceptions arising from sounds are called dhvanis (_Vāk._ 103). As by the movement of water the image of a thing situated elsewhere also appears to adopt the movement of the water and thus seems to move, so also the sphoṭa, though unchanging in itself, yet appears to suffer change in accordance with the change of nāda which manifests it (_Vāk._ 49). As there are no parts of the letters themselves so the letters also do not exist as parts of the name. There is again no ultimate or real difference between names and propositions (_Vāk._ 73). It is only in popular usage that they are regarded as different. That which others regard as the most important thing is regarded as false here, for propositions only are here regarded as valid (_Vāk._ 74). Though the letters which manifest names and propositions are altogether different from them, yet their powers often appear as quite undifferentiated from them (_Vāk._ 89). Thus when propositions are manifested by the cause of the manifestation of propositions they appear to consist of parts when they first appear before the mind. Thus, though the pada-sphoṭa or the vākya-sphoṭa does not really consist of parts, yet, as the powers of letters cannot often be differentiated from them, they also appear frequently to be made up of parts (_Vāk._ 91).