This book analyses a particular religious identity that developed amongst the adherents of a distinctive body of beliefs in the last thirty years of the eighteenth century, often in an atmosphere of hostility, against a background of fear, and in a derogatory manner. It explores attempts by Rational Dissenters to define, explore, and justify the theological ideas that formed the basis of their distinctive characteristics, together with the evolution of their identity in this context.

The study of a wide range of individuals, ministers, laymen and women, Arians, and Unitarians, who adhered to Rational Dissenting theological ideas, allows a far broader perspective, and analyses in greater depth, of a number of elements in the makeup and evolution of Rational Dissent than any study based principally on Richard Price and Joseph Priestley. This approach highlights statements in which Rational Dissenters specifically made the point that Price and Priestley were not representative of their views and methods, and that the development of theological arguments amongst Rational Dissenters reached very different conclusions from those of Price, and in particular those of Priestley. Greater diversity within Rational Dissent than has previously been acknowledged is evident. Rational Dissenting published authors are examined on the one hand, and on the other, their readers are identified through their financial subscriptions to such works and their borrowing habits as members of Unitarian chapel vestry libraries. This approach illuminates the nature of the appeal of Rational Dissent in a way that no focus on Price and Priestley, two untypical polymaths, could hope to do.

The key conclusion emerging is the overwhelmingly theological nature of the identity of Rational Dissent, in contrast to a secular focus apparent in many historiographical studies. The distinctive nature of Rational Dissenting theology had a major impact on the nature of commitment by its adherents in the later eighteenth century to progress and liberty, as they perceived them. Previous scholars have referred to the co-existence of the rejection of three doctrines, those of original sin, atonement, and predestination, with an optimistic belief in the possibility of progress for all mankind. This research establishes that this optimistic concept was the direct result of Rational Dissenting dismissal of these doctrines. These theological ideas not only drove their notions as to the nature of society but also made them in their reformism more inclusive and progressive than Orthodox Dissenters or members of the Established Church.