In addition to a history of previous catalogues, his abhorrence of plagiarism and his attack on Dryden, the Preface contains statements of Langbaine's own literary interests and critical principles. He had an obvious "_relish of the_ Dramma" (A2r) which probably dated from the time he was "bound an Apprentice to a Bookseller called Nevil Simmons living in S. _Paul's_ Church Yard in _London_." This time spent in London, from about 1667 to 1672 was probably his greatest period of play-going.[23] His orientation, however, is not toward the performed play. He sees drama as essentially the history of the printed work and, unlike John Downes in _Roscius Anglicanus_ (1708), he approaches the appreciation of plays through criticism ([a3v]). Like his father, the sometime provost of Queen's College, Oxford, who left behind him "rhapsodies of collections,"[24] he was an antiquarian and bibliographer. He had the bibliographer's delight in the difficulty of the search ([A3v]) and his pleasure in ordering. _Momus_ is designed for those readers who "_may possibly be desirous, either to make a Collection, or at least have the curiosity to know in_ general, _what has been Publish't in our Language, as likewise to receive some Remarks on the Writings of_ particular _Men_" (A2r-[A2v]). As this statement suggests, his general literary principles are neo-classically sound and standard: "it being nobler to contemplate the general History of Nature, than a selected Diary of Fortune" ([A4v]), as is his unprejudiced attitude toward borrowings and the need for models. For Langbaine the end of literature is moral, "Decency _and_ Probability" ([A4v]), and there is a sense of balanced fairness which extends even to Dryden:
Mr. _Dryden_ has many excellencies which far out-weigh his Faults; he is an excellent _Critick_, and a good _Poet_, his stile is smooth and fluent, and he has written well, both in Verse and Prose. I own that I admire him, as much as any man ... ([a2v], italics reversed).
But, in the case of Dryden, the fairness is much a matter of strategy and the balance is partly stylistic. Langbaine's praise has the perfunctory quality of "Well, now that's out of the way," and, characteristically, the praise is followed closely by an intensely felt "but" clause which excoriates Dryden for his immodesty in debate and his misuses of literature. Langbaine's language is often that of theology, the "right Path to solid Glory" ([a2v-a3r]), and he intends to show that many authors (and especially Dryden) "_have fallen into very great Errours_" ([A3r]).