Mesle is the author of ''Process Theology: A Basic Introduction''. In this book he outlines three attributes of a process theology. There is a relational character to the divine such as:
*God experiences both the joy and suffering of humanity.
*God is not omnipotent in the classical sense
*God exercises relational power and not unilateral control.
In chapter 17, he formulates a process naturalism. As a naturalist his religious view is one without a divine being. There is only the finite world. His process naturalism shares with process theism recognition of the ambiguity of Existence. It also has virtually every value and ethical standard in common with process theism and religious in this respect. Consequently, Mesle is a religious naturalist.
