The concept of intrinsic evil has undergone a renaissance in the official moral teaching of the Catholic Church in the second half of the twentieth century and became one of its pillars. Used for centuries almost exclusively in relation to moral judgements on issues in sexual ethics (masturbation, homosexual acts, contraception, etc.), its modern rendition has expanded its scope so that it can now seemingly be used in relation to social ethics (genocide, slavery, deportation, etc.) and politics (i.e., the U.S. bishops' instructions on how to vote) as well. That alone justifies analysing it as a case study in the development of moral doctrine. However, such an analysis brings forth additional questions related to the issue of the development of moral doctrine. Namely, as one ponders over the various meanings of notions contained in the typical definition of intrinsically evil acts as those acts that are always evil (bad? wrong?) on the basis of their object, no matter the intention or circumstances, one will become aware that the moral doctrine might be currently operating with two or more concepts of intrinsic evil with no indication of which is/are normative. This problem is further exacerbated by the role of tradition in its genealogy, which complicates a simple appeal to tradition in order to resolve it and necessitates a more nuanced understanding of tradition as the central notion within any discussion on the development of (moral) doctrine.