In the "Treatise of Human Nature," David Hume claims that we are determined to hold certain unavoidable and necessary beliefs that have been termed 'natural beliefs' in the literature: the beliefs in causal power, the external world and the self. This book is concerned with establishing whether or not the belief in an intelligent designer, as expressed by Philo's 'irregular argument' in Humes's "Dialogues Concerning Natural Religion," can be included in the classification of 'natural belief'.