Is reductionism simply a methodology that has allowed science to progress to its current state (methodological reductionism), or does this methodology indicate something more, that the material universe is determined in full by its smallest components (ontological or causal reductionism)? Such questions lie at the heart of much of the contemporary religion–science dialogue. In this essay I suggest that the position articulated by philosopher–theologian Bernard Lonergan is particularly suitable for dealing with these questions. For Lonergan, the criterion of the real (...) is simply its verified intelligibility and not its imaginability. Each of the various levels of reality, as studied in sciences such as physics, chemistry, biology, and sensitive and rational psychology, consists of an intelligible integration of what on the lower level would be simply random occurrences. The things studied by the various sciences (atoms, molecules, cellular organisms, animals, human persons, and so on) are intelligible unities, and no one level is somehow more real than any other. I argue that such a scheme, while seeming somewhat counterintuitive, is best able to deal with the multilayered reality of the contemporary physical and life sciences and provide an opening to the richness of the social sciences and the achievements of human culture. (shrink)