White adds: “How God can know future events, for example, and yet not determine them, is an important point….” (Debating Calvinism, p.163, emphasis mine)
So in other words, God can only know what He determines. That doesn’t do much for omniscience, and also leaves no room for Middle Knowledge, which is the knowledge of all possible choices. According to Calvinism, God would have to determine all of the possible choices too, in order to infallibly know them. Since all possible choices are infinite, God would have to determine something that is infinite. It would be interesting to see a Calvinist try to explain that.