The Pali term ‘vinnyaanam’ is formed from ‘vi’+ ‘nyaa’ + ‘yu’.
As you know, ‘vi’ is an adverb suffix. ‘nyaa’ is a verb root called ‘dhaatu’ while ‘yu’ is a suffix to make a noun from a verb root.
So, ‘vinnyaanam’ is a noun formed from a verb. It is not a participle.
The definition of ‘vinnyaanam’ is “aaramanam vijaanaatiiti vinnyaanam”.
“It is called ‘consciousness’ because it knows a stimulus.”
Thus, when ‘vinnyaanam’ is found in the context of knowing a stimulus, it should be translated as consciousness.
However, when ‘vinnyaanam’ is found in the context of indicating ‘nibbaana’, it should be translated in the passive voice as done by the commentary on Kevatta Suttam in Siilakkhandhavagga Diighanikaaya Atthakathaa.
“Vinnyaatabbanti vinnyaanam nibbaanassetam naamam.”
“It is called ‘Knowable’ because it is known uniquely; it is the name of nibbaana.”
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