While the critical attack on Turner by the periodical press may have provided the immediate impetus to the composition of Modern Painters I, the circumstances which gave rise to the work are more complex. Its deeper roots lie in Ruskin 's Evangelical beliefs. By attempting to make aesthetic appreciation a matter of private judgment rather than unquestioning adherence to the institutional principles of the Royal Academy, Ruskin hoped to give art and art criticism a religious and moral role.
The 'germ' of Modern Painters I, Cook and Wedderburn argue, was Ruskin's letter, never sent, written in response to the attack on Turner's paintings in the Royal Academy exhibition of 1836 by Blackwood's Magazine (1. xxxiii). According to Ruskin, the origin of Modern Painters I, or 'Turner's work' as he described it, was his resolution, made on 6 June 1841, 'to be always trying to get knowledge of some kind or other... or some real available, continuing, good, rather than mere amusement of the time'. The diary entry recording this decision, made while attending a Church service in Geneva, was later annotated by him as 'the most important entry in all the books' (see Evans and Whitehouse, Diaries I, p.199).
The possibility of a career as a cultural critic was intimated by the publication of Ruskin's series of essays on architecture which appeared in the Architectural Magazine (1837-1838) and published in book form as The Poetry of Architecture (1893). Letters to his friends, the Rev. Edward Clayton and Henry Acland, written while Ruskin was at Oxford in the early 1840s, indicate that he was beginning to develop the aesthetic arguments which underpin Modern Painters I (see Works, 1.420-472 and 36.19-21, 23).
Ruskin's travels on the Continent during 1840-1841, following the breakdown of his health, enabled him to experience the art and architecture of France and Italy at first hand. His art education was further broadened by his friendship with the artists, George Richmond and Joseph Severn, whom he met in Rome early in 1841. That Modern Painters I was begun during this period is suggested by Ruskin's letter, written on 12 February 1841, telling Clayton that he had started 'a work of some labour which would take me several years to complete' ( Works, 1.435).
Ruskin's enthusiasm for art, however, threatened to compromise the future in the Church of England for which his Evangelical parents hoped. Ruskin outlined his dilemma to his former tutor, the Rev. Thomas Dale, in September 1841: refusing to distinguish between the duty of 'laymen' and 'churchmen' to save souls, Ruskin argued that he would be more successful in achieving this goal through art rather than through religion (see Works, 1.395-398). It is possible that he was inspired by Thomas Carlyle's lectures, later published under the title, On Heroes and Hero-Worship, reviews of which Ruskin was reading in June 1841. (See Works, 36.25). Carlyle had written: 'the writer of a Book, is he not a Preacher preaching... to all men in all times and places?'
It would seem that Ruskin began collecting material for Modern Painters I during 1842, making extensive notes on paintings by Rubens during his visit to Antwerp in August that year. By 31 January 1843 he noted that 'his stuff' was 'getting a little into shape at last' ( Evans and Whitehouse, Diaries I, p.241), his visits to the Dulwich Gallery and the National Gallery in subsequent months also recorded in his diary. On 1 May 1843 he wrote: 'Couldn't write while I had this work for Turner to do; had not the slightest notion what labour it was' ( Evans and Whitehouse, Diaries I, p.245).