Significance and System: Essays on Kant's EthicsSignificance and System: Essays on Kant's Ethics brings together central lines of thought in Mark Timmons's work on Kant's moral theory. The first part of the book concerns the interpretation and justification of the categorical imperative in which Timmons argues for a differential roles interpretation of the categorical imperative, according to which distinct formulations of this principle play different roles in the overall economy of Kant's ethics.