Thomas Gainsborough has been celebrated as a lanscapist whose pictures evoke his love of the countryside, as a portrait painter of exactness and vivacity, and as a rhythmic and spontaneous draughtsman. Such judgements have persistently created a difficulty for art criticism. Gainsborough's work is not satisfactorily accounted for by the classicizing academic criteria which aspired to be the official art theory of his period. It is not sufficient to label him an anti-intellectual, natural genius. Paying equal attention to portraits, landscapes and fancy pictures, this work aims to demonstrate that Gainsborough's work demands an alternative explanatory framework. Analysis of individual pictures, supp orted by illustrations and citations, suggest a variety of 18th-century contexts for Gainsborough's achievements: the populist and emotive culture of religous non-conformity; a philosophical and scientific outlook, epitomized by John Locke and Isaac Watts, based on self-scrutiny and careful observation of the external workd; pastoral and emblem literature; 18th-century music theory; and the work of writers including John Bunyan, Francis Quarles, Jonathan Edwards; William Cowper and Laurence Sterne. Pictorial analyses clarify Gainsborough's relationship with the work of his artistic contemporaries and predecessors, notably Hogarth, Hayman, and Reynolds; Rubens, Van Dyck, Ruisdael, Claude and Watteau. The authors aim to reveal that the style, themes, and ideas of Gainsborough's images constitute purposeful expressions of an intellectual and visual culture of the 18th century.