"If ever I write any more epistles in verse, one of them shall be addressed to you. I have long concerted it, and begun it; but I would make what bears your name as finished as my last work ought to be, that is to say, more finished than any of the rest. The subject is large, and will divide into four epistles, which naturally follow the Essay on Man; viz. 1. Of the extent and limits of human reason and science. 2. A view of the useful, and, therefore, attainable, and of the unuseful, and, therefore, unattainable, arts. 3. Of the nature, ends, application, and use, of different capacities. 4. Of the use of learning, of the science of the world, and of wit. It will conclude with a satire against the misapplication of all these, exemplified by pictures, characters, and examples." This work in its full extent, being now afflicted with an asthma, and finding the powers of life gradually declining, he had no longer courage to undertake; but, from the materials which he had provided, he added, at Warburton's request, another book to the Dunciad, of which the design is to ridicule such studies as are either hopeless or useless, as either pursue what is unattainable, or what, if it be attained, is of no use. When this book was printed, 1742, the laurel had been, for some time, upon the head of Cibber; a man whom it cannot be supposed that Pope could regard with much kindness or esteem, though, in one of the imitations of Horace, he has liberally enough praised the Careless Husband. In the Dunciad, among other worthless scribblers, he had mentioned Cibber; who, in his Apology, complains of the great poet's unkindness as more injurious, "because," says he, "I never have offended him." It might have been expected, that Pope should have been, in some degree, mollified by this submissive gentleness, but no such consequence appeared. Though he condescended to commend Cibber once, he mentioned him afterwards contemptuously in one of his satires, and again in his epistle to Arbuthnot: and, in the fourth book of the Dunciad, attacked him with acrimony, to which the provocation is not easily discoverable. Perhaps he imagined, that, in ridiculing the laureate, he satirized those by whom the laurel had been given, and gratified that ambitious petulance, with which he affected to insult the great. The severity of this satire left Cibber no longer any patience. He had confidence enough in his own powers to believe, that he could disturb the quiet of his adversary, and, doubtless, did not want instigators, who, without any care about the victory, desired to amuse themselves by looking on the contest. He, therefore, gave the town a pamphlet, in which he declares his resolution, from that time, never to bear another blow without returning it, and to tire out his adversary by perseverance, if he cannot conquer him by strength.