In Religious Language and Complementarity, the author develops an analogy between the structure of the Copenhagen Interpretation of quantum mechanics and theological systems, with particular emphasis on the theology of correlation of Paul Tillich. The author points out the limits of this analogy and evaluates the effectiveness of the analogy as a defense against the charge that the prima facie inconsistency of traditional Christian theological systems is a genuine inconsistency. Contents: "Theology and Falsification" Revisited; The Language of Immutable Attributes and the Language of Dialogue; Christian Theology and the Two Languages: A Brief Historical Survey; The Orwellian Challenge: Assumptions and Options; Omnipotence and Dialogue; Theology in the Language of Immutable Attributes; Theology in the Language of Dialogue; Bultmann's Existentialist Alternative; The Copenhagen Interpretation of Quantum Mechanics; Tillich's Theology of Correlation; Theology of Correlation and the Copenhagen Interpretation: A Cogent Analogy?; "As If" Interpretations and Cognitive Significance; Recapitulation.