In a critique of Open Theism, Tim Chaffey lists out several dangers of Open Theism (he is summarizing Richard Mayhue). Number seven reads:
7) Boyd’s position diminishes the Almighty’s deity.
This is a more formal version of a common claim against Open Theism: “if God were to not know the future then He would not be God.”
Darrell Berkley writes on the Facebook group God is Open:
Darrell Birkey I remember years ago when a friend at church asked me. “What if God doesn’t exhaustively know the future?”
Later that day at lunch with friends, I asked the same question and the reply was, “If He didn’t exhaustively know the future… He wouldn’t be God!”.
I responded, “Wouldn’t He just be different than the God of your imagination?”
God made man in His image and likeness. When we try to make God in our image and likeness, we can attribute some very bad things to God.
It is wrong to presume attributes as to what God “must” be like. This is the Dignum Deo fallacy. Because human beings do not have the luxury of creating reality through introspection, our thoughts on what “should be” have zero effect on what is actually. To illustrate:
A man might think: “a perfect wife is kind, sensitive, attractive, and patient”. But if he observes his own wife, it is a mistake for him to assume these attributes on her and then reinterpret all her actions such as to fit these attributes. Someone based in reality will instead observe the behaviors of his wife and then attribute attributes to her based on past experience. Introspection does not lead to truth. Observable evidence leads to truth.