The main theoretical issues in the study of the history of the Archaean Controversy in Britain, which arose in the first three papers of the present series, are summarized and discussed—in particular the problem of stratigraphical work in rocks where no fossils can be discerned. The ‘Archaean’ geologists showed some leanings towards Neo-Neptunism and this, together with the fact that their work challenged the Murchison/Survey view of British geology, was one of the reasons for the controversy. At a deeper level, (...) however, the question concerned the doctrine of uniformitarianism: Were metamorphic rocks to be found at any part of the stratigraphical column, or were they confined to the earliest period of the Earth's history? The establishment of the concept of Precambrian rocks and a suitable stratotype boundary is essentially a social question that has to be determined within the geological community. Some of the social processes whereby these matters are decided internationally are considered, and it is noted that the best location of the ‘Golden Spike’ for the Precambrian/Cambrian boundary has only just been settled . The paper also explores some nineteenth-century ideas about the nature of metamorphism, and the early conditions of the world. (shrink)