For reasons I do not understand, the editors of the Nicene/Post-Nicene Fathers series chose not to include St. Augustine’s On Free Choice of the Will in the set. You may find the set online (organized differently than the actual books) here; you will not find this work there, however (nor, as far as I can determine, in the actual books).
Consider the following, taken from the introductory materials in this edition:
A work which is the highwater mark of [Augustine’s] philosophical writing.
The book is especially noteworthy in that it sets out in greater detail than any of Augustine’s other works, large or small, his major argument for the existence of God: the argument to eternal truth.
Certainly Augustine continued to regard it highly as a medium for the expression of his ideas.
There is no doubt, then, that Augustine and his associates considered the work of great importance.
And yet, for some odd reason, the editors of N-PNF didn’t consider the book worthy for inclusion.
Perhaps we may make a guess from the fact that Schaff labeled it an “anti-Manichaean” work (Nicene and Post-Nicene Fathers, First Series, Volume 1; p. 16); considering our book’s small size, maybe he thought other works better represented the Saint’s thought on the subject. But aside from the opinions above concerning the value of the work, the translator also points out (p. xxv) that On Free Choice of the Will presents Augustine’s attempt at addressing the problem of evil. This is not merely an antiquarian question, then, of interest primarily to historians, but is likewise valuable today (and for those of us with a Thomistic bent of some sort, the book is interesting in that we get a fair idea of how Aquinas was influenced on that score by Augustine; maybe someday I’ll be able to post about that. But I digress).
I’m probably going to write a few posts based upon the book, and so we come to the real purpose of this post: I’m not going to be able to offer links to the book online, because it does not appear to be available. So, dear reader (assuming that I have any readers…), you must content yourself with the quotations I offer, or you’ll have to get a hard copy of the book. Sorry.
Aquinas, Etc. 
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