Recent years have seen an increasing focus on the right ordering of human sexuality as a marker of 'orthodoxy' in the church. Many arguments, in different communions, have focused on particular Biblical texts, natural law, patristic writing, or wider Tradition, with a perplexing lack of engagement with questions of culture and societal norms, or on matters of natural science, psychology, or anthropology. This has led to a situation in which theologians posit answers to incomplete questions, and in which doctrine has been forced to adopt a stance - that of concreteness despite opposing evidence - which it cannot withhold. The Church of England has recently embarked on renewed debates on sexuality, sex and gender, which have reflected this unfortunate emphasis and pattern. In this paper, we will address what the sciences - social, biological, psychological - might have to contribute to our understanding of theological anthropology, consider why this remains a marginalised area, and argue that a debate on questions of morality must first be addressed through engagement with properly informed understandings of the human person. We will consider the degree to which recent theological arguments in the Living in Love and Faith process have successfully done so, analyse the usefulness of traditional understandings of 'doctrinal development' in these conversations, and challenge the neat distinction drawn between pastoral practice and doctrinal purity.