In the late 1810s and 1820s the Edinburgh phrenologists were largely concerned with trying to establish phrenology as the true science of mind. They challenged the accepted theories about the nature of mind and the brain; in turn, phrenology was attacked by the proponents of Scottish common-sense philosophy and by some medical men. The ensuing debate, which is discussed as an example of conflict between incommensurable world-views, involved a wide range of contentious theological, philosophical, scientific and methodological issues.

This account of the conflict between phrenologists and anti-phrenologists in early nineteenth-century Edinburgh is offered as a case study in the sociological explanation of intellectual activity. The historiographical value and propriety of a sociological approach to ideas is defended against accounts which assume the autonomy of knowledge. By attending to the social context of the debate and the functions of ideas in that context one may construct an explanation of why the conflict took the course it did.