To defend free will was not, of course, to insist on the operation of pure chance. Most thinkers still saw objective chance as virtually impossible, and few were prepared to identify the rational will with it. But at least the connotations of chance had changed. Previously it had seemed impiuous to allow chance a role in the world, as if God did not attend to every sparrow. Now chance stood for the incompleteness of mechanical law, for the possibility of non-material causation.
Gerd Gigerenzer
et al.,
The Empire of Chance, section 2.6.
This joins the defense of free will laid down by K. Popper as I noticed in this
post and this
note. See also this
post as well as
the work on incompleteness by Gregory Chaitlin.