Now, in his leisure time, he read over various works of a theological character, and came to the general conclusion that "the study of polemics or Biblical critics will tend neither to settle principles nor clear up doubts, but rather to confuse the former and multiply the latter." Prescott's whole religious creed was, in fact, summed up by himself in these words: "To do well and act justly, to fear and to love God, and to love our neighbour as ourselves--in these is the essence of religion. For what we can believe, we are not responsible, supposing we examine candidly and patiently. For what we do, we shall indeed be accountable. The doctrines of the Saviour unfold the whole code of morals by which our conduct should be regulated. Who, then, whatever difficulties he may meet with in particular incidents and opinions recorded in the Gospels, can hesitate to receive the great religious and moral truths inculcated by the Saviour as the words of inspiration? I cannot, certainly. On these, then, I will rest." In April, 1838, Prescott took the first step toward beginning a study of the Mexican conquest. He wrote to Madrid in order to discover what materials were available for his proposed researches. At the same time he began collecting such books relating to Mexico as could be obtained in London. Securing personal letters to scholars and officials in Mexico itself, he wrote to them to enlist their interest in his new undertaking. By the end of the year it became evident that the wealth of material bearing upon the Conquest was very great, and a knowledge of this fact roused in Prescott all the enthusiasm of an historical investigator who has scented a new and promising trail. Only one thing now stood in the way. This was an intimation to the effect that Washington Irving had already planned a similar piece of work. This bit of news was imparted to Prescott by Mr. J. G. Cogswell, who was then in charge of the Astor Library in New York, and who was an intimate friend of both Prescott and Irving. Mr. Cogswell told Prescott that Irving was intending to write a history of the conquest of Mexico, as a sort of sequel, or rather pendant, to his life of Columbus. Of course, under the circumstances, Prescott felt that, in courtesy to one who was then the most distinguished American man of letters, he could not proceed with his undertaking so long as Mr. Irving was in the field. He therefore wrote a long letter to Irving, detailing what he had already done toward acquiring material, and to say that Mr. Cogswell had intimated that Irving was willing to relinquish the subject in his favour.