Apophatic theology is another name for “theology by way of negation,” according to which God is is known by negating concepts that might be applied to him, stressing the inadequacy of human language and concepts used to describe God. Philo and Plotinus influenced the Christian apophatic tradition, which is founds in the works of Gregory of Nyssa and Pseudo-Dionysus the Areopagite.
It is characteristic of mystic theology and Eastern Orthodox; and shows parallels with Indian Advaita Vedanta. A.G.H.
Source:
Bowker, John, The Oxford Dictionary of World Religions, New York, Oxford University Press, 1997, p. 81