An analysis of relevant aspects of the history of science shows that theology's loss of credibility in an increasingly science-oriented age can be attributed to unresolved disputes from the past over metaphysical, epistemological and methodological issues. In Chapters 1 and 2, an attempt is made to show that the basic disagreements between science and theology can be traced to the ongoing quest for the principles of knowing shared by all disciplines. In Chapters 3 to 6, an attempt is made to identify these principles. Firstly, the processes and principles by which science acquires its knowledge and deems it to be objective are examined. Secondly it is argued that these same processes and principles are not the special property of science but are used by the humanities as well. Thirdly, it is contended that these principles are "empirico-critical." They enable us to bridge the gap between thought and reality and gain access to knowledge of the external world. A more comprehensive model for knowing is proposed. Chapters 7 to 9 examine whether it is possible to apply empirico-critical principles to theology. From a study of relevant aspects of Austin Farrer's thought, it is argued (i) that the processes of knowing in theology are the same as those in the sciences and the humanities, (ii) that, though theology's procedures and techniques are necessarily different from, say, the sciences because of its subject matter, these are capable of adhering to the same principles of objectivity, and (iii) that, in principle, theological decision-making is possible, even in the most controversial debates. The conclusion is that since the same processes and principles of trustworthy knowing in the sciences and humanities are fully applicable to theology, theology's viability as a source of trustworthy knowing should no longer be held in doubt.