This is my major thesis. Mystery is inherent in both the nature of things and the nature of rationality. I will sustain this thesis by a review of some of the central issues of philosophy to elucidate their mysterious qualities. More important, however, I will develop in detail an explanation of mystery and trace some of its important ramifications.

I will argue that an ordinal metaphysics, with its associated theory of query, provides an account of mystery that no other theory can provide.
While the theory presented here is a theory of philosophical mystery, it has fundamental implications for all branches of knowledge, including the physical and social sciences.
In short, I speak against a simplistic view of the world and of experience based on a simplistic and narrow conception of understanding and rationality. Mystery calls not for veneration and awe, but for a full and complex activity of mind, broaching all established conditions in its pursuit of answers…Reason is fulfilled as completely in mysteries which persevere throughout our efforts to resolve them as in mysteries which are resolved and dissipated, passing into new questions to which we must find new answers, in an unterminating process of rational interrogation.

• From the Preface by Stephen David Ross