Prameya means direct perception. Aprameyah means one which cannot be defined, explained or measured.
In the physical world normally everything is defined by one of the following means – Direct Perception; By Inference and By Authoritative Scriptures like Vedas. These are also Known as Anumana Pramana, Pratyaksha Pramana and Shabda Pramana.
nrnam nihsreyasarthaya vyaktir bhagavato nrpa
avyayasyaprameyasya nirgunasya gunatmanah (SB 10.29.14)
O King, the Supreme Lord is inexhaustible and immeasurable, and He is untouched by the material modes because He is their controller. His personal appearance in this world is meant for bestowing the highest benefit on humanity.
We can understand that the Supreme Lord cannot be understood or measured by our limited senses. Our eyesight is limited to a particular distance, beyond which we cannot see. Our ears can listen up to some decibels, beyond which we cannot hear. With such limitations, we cannot measure the Supreme creator, controller and the protector of all living and non-living entities. We can understand the Lord only to some extent but not completely its like getting the ocean home. We can only get a pot full of ocean water home, but not the entire ocean, if we do, we know we would only become homeless!!
Lets chant the Holy Name of the immeasurable person and seek to understand Him with all our limitations to develop true Bhakti and render Devotional service.
Nama 46 – VishnuSahasranama