Aquinas holds that after death, the human soul can no longer change its basic orientation either toward God or away from him. He takes this to be knowable not only from divine revelation but by purely philosophical reasoning. The heart of his position is that the basic orientation of an angelic will is fixed immediately after its creation, and that the human soul after death is relevantly like an angel. This article expounds and defends Aquinas's position, paying special attention to the action theory underlying it.
This is a topic I’ve written about here at the blog, but this new academic article explores it more systematically and in greater depth. I will also be addressing it in the book on the soul and I have been working on for some time and hope to finish by year’s end.