Roger Olson, a classical Arminian, defends Open Theism from those who would call it Process Theology:
So what are the differences? All open theists affirm creatio ex nihilo while process theology denies it. All open theists affirm God’s omnipotence while process theology denies it. All open theists affirm the supernatural and miracles while most, if not all, process theologians deny them. Open theists all say that God limits himself; process theology represents God as essentially limited and finite. The only point on which they agree is about God’s knowledge of the future, but even there one finds profound differences. For example, according to open theists the openness of the future even for God is due to God’s self-limitation in creation. According to all open theists, God could know the future exhaustively and infallibly IF he chose to create a world with a closed future (as in divine determinism).
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