। ॥ ३२२ ॥
In plain words
He is called Prājña, and rightly so, because what he lights up is one ignorance — a single one. Individual scale is the lesser scale, so he does not light up ignorance in the plural.
Close to the Sanskrit
The state of being Prājña is, for this one, accepted by reason of its being the illuminer of a single ignorance; because of the lowliness of the individual, of this one there is no illumining of manifold ignorance.