What is Idem Est Nihil Dicere Et Insufficienter Dicere?

Legal Definition
It is the same thing to say nothing, and to say a thing insufficiently. 2 Inst. 178. To say a thing in an insufficient manner is the same as not to say it at all. Applied to the plea of a prisoner. Id.
-- Black's Law Dictionary
Legal Definition
It is the same thing to say nothing as not to say enough.
-- Ballentine's Law Dictionary