He brings Jonathan Edwards and Jean Calvin into the argument, too. I find it fascinating how much Edwards and Harris have in common, arriving at like conclusions though coming from different directions. You might find it interesting:
http://www.booksandculture.com/articles/2013/janfeb/bait-and-switch.html?paging=off
Clearly a lot of this argument (all of it, maybe) hangs on how you define "free will."
While Plantinga writes with a gentle, light wit, he actually confuses the issue. There are at least four definitions used of free will in his article, muddling the real questions. Ill see if I can set them out (and their proponent), then isolate the real questions:
1. Harris
Free will means the capacity to identify and control all factors in the universe which might impact a persons decisions. There is no God so these are undirected factors caused by an unthinking universe governed only by chance, time and partially understood random inputs. Free will requires maximal autonomy.
2. Plantinga
Free will means the capacity to recognize that in most situations a man intentionally selects a given path of behavior. The man does not need to know exactly what inputs brought the selection about; he only needs to be aware that he contributed to the selection. In the event physical maladies exist, the person may not be free.
3. Ascribed to Calvin
Free will means the capacity to choose between good and evil, or specifically the capacity to select a given path of performing good acts in either a sinful manner or performing them in an utterly good (righteous) manner. It does NOT mean one is not completely free to select Merlot over Cabernet Sauvignon.
4. Ascribed to Edwards
Free will means the capacity to believe/think/act entirely without influence by God. God could not be the real cause of everything if free will is to exist.
Mrs. Don-O, you have rightly implied that unless two (or more) agree on what free will actually is, the discussion is fruitless. My point to Pope Pius XII was that the only really valuable definition is Edwards. The others, whether they represent enjoyable discussions or not, simply do not get to crux of the matter.
I can dismiss Harris definition out of hand as the product of an athiest. I find Plantingas definition missing the mark, also. The red sox, green sox definition does not get behind the choosing. I have read Calvins Institutes and find both Plantingas & Mullers remarks too abbreviated to be seriously considered representative. As Plantinga said, however, much ink has been spilt on this topic, so I wont go there.
But, with Edwards I believe we can extract a definition that is sufficiently distinctive to begin a discussion. I am not asking Pope Pius XII to agree that there is no such thing as free will, only to recognize that Edwards definition gets to the heart of the matter. And, if we limited our discussion temporarily to just salvation, the picture sharpens:
Are we free from God enough that it is entirely up to us to determine whether we alone decide to trust Jesus Christ, the Rescuer from Israel? Is each man/woman the captain of his ship, the master of his/her destiny? Or is each person who trusts Him guided/managed to that place by Gods active work in that specific persons life? This second option implies that the person would not have faith were it not for this active work by God, and not all people are given this active work.
Here is where the real sparks fly.