In his influential philosophical work Insight, Bernard Lonergan made the intriguing and problematic claim that "the polymorphism of consciousness is the one and only key to philosophy." In Lonergan on Philosophical Pluralism, Gerard Walmsley examines Lonergan's many discussions of the different forms of human consciousness, as well as his sustained responses to the problems raised by philosophical and cultural pluralism.

Looking closely at Lonergan's thoughts on patterns of experience, different levels of consciousness, and the differentiations of consciousness that occur...