Butler was a major, even at times a dominant, figure in the Enlightenment, Romantic and Victorian periods, so that the case for a refreshed reading of his works scarcely needs arguing. We have reviewed, and in some instances criticized, the enormous range of thinkers who drew on him and noted the multitude of seemingly incompatible narratives to which he was acknowledged, or claimed, to have contributed. An exploration of this proliferation of Butlers, and Butler's contribution to anglophone intellectual and social history, cannot be done unless we also agree to investigate what he actually said. Regrettably, we have noted instances – and passed over many more – of philosophers and scholars unashamedly deriving their readings from anthologies or third-party accounts. Moreover, the situation is complicated by the absence of reliable texts. All posthumous editions are, to varying extents, inaccurate and misleading: in particular, Fifteen Sermons needs a variorum edition. The minor works and manuscript fragments have not yet been transcribed and edited accurately. With some of Butler's writings, therefore, the present book produced attempts at publishing the first developed readings (notably Chapters 4 and 5), while with the Clarke letters and Fifteen Sermons it required in effect the preparation of new editions. The twentieth-century Anglo-American approach to Butler was set aside; it tended to offer a stimulating but secularized figure, deficient in terminological rigour, playing anachronistically to weaknesses some of which he would have denied were such. The fairly small body of recent good work about him has not succeeded in setting Butler studies on a scholarly basis or reassessing his legacy. The starting point for the present book has therefore been one fact of fundamental importance: that his work was pastoral and apologetic, motivated and defined by his ministerial vocation.

For Butler the human reason was primarily a survival mechanism, poorly fitted for speculation and systematic thought: the ethical person must struggle unremittingly to become human. Locke had proposed that the mind was a tabula rasa but, in conscious opposition to this, Butler denied that it was solely a processor and store of information. He set the reception and construction of knowledge within psychological affective mechanisms, which produced mental states in which knowledge and emotions were formally inseparable and to be described in ethical terms. Edmund Wilson's phrase, ‘the shock of recognition’, could have been invented for him.