Slight mistakes on either side are little blamed, but grave and conspicuous cases incur severe censure.

Yet how far the censure ought to go, is difficult to lay down beforehand in general terms.

There is the same difficulty in regard to all particular cases, and all the facts of sense: which must be left, after all, to the judgment of Sensible Perception [Greek: aisthaesis].
Book Third takes up the consideration of the Virtues in detail, but prefaces them with a dissertation, occupying five chapters, on the Voluntary and Involuntary.

Since praise and blame are bestowed only on voluntary actions,--the involuntary being pardoned, and even pitied,--it is requisite to define Voluntary and Involuntary.

What is done under physical compulsion, or through ignorance, is clearly involuntary.