Pseudo-Dionysius (about 500 CE), or ‘Fake Dennis’, was a Syrian Christian who read Augustine and other authors and was big into negative theology and kataphania.  He was thought to have been the original Dionysius, the first Catholic Bishop of Athens, but modern scholarship has shown that he could not have been based on his texts.  He argued that the journey to the One was essentially one of unknowing and the One was the great Unknown, above all qualities or being.