“Augustinian” is synonymous with “Reformed”, “Calvinist”, and “Classical Theists”. They are closely related to the philosophy of Plato. From Augustine:

If, then, Plato defined the wise man as one who imitates, knows, loves this God, and who is rendered blessed through fellowship with Him in His own blessedness, why discuss with the other philosophers? It is evident that none come nearer to us than the Platonists. -City of God, 8.5

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