De Quincey divides his writings into three groups: first, that class which "proposes primarily to amuse the reader, but which, in doing so, may or may not happen occasionally to reach a higher station, at which the amusement passes into an impassioned interest." To this class would belong the _Autobiographic Sketches_ and the _Literary Reminiscences_. As a second class he groups "those papers which address themselves purely to the understanding as an insulated faculty, or do so primarily." These essays would include, according to Professor Masson's subdivision, (a) Biographies, such as _Shakespeare_ or _Pope_--_Joan of Arc_ falls here, yet has some claim to a place in the first class; (b) Historical essays, like The _Cæsars_; (c) Speculative and Theological essays; (d) Essays in Political Economy and Politics; (e) Papers of Literary Theory and Criticism, such as the brilliant discussions of _Rhetoric, Style_, and _Conversation_, and the famous _On the Knocking at the Gate in 'Macbeth_.' As a third and "far higher" class the author ranks the _Confessions of an English Opium-Eater_, and also (but more emphatically) the _Suspiria de Profundis_. "On these," he says, "as modes of impassioned prose ranging under no precedents that I am aware of in any literature, it is much more difficult to speak justly, whether in a hostile or a friendly character." Of De Quincey's essays in general it may be said that they bear witness alike to the diversity of his knowledge and the penetrative power of his intellect. The wide range of his subjects, however, deprives his papers when taken together of the weight which might attach to a series of related discussions. And, remarkable as is De Quincey's aptitude for analysis and speculation, more than once we have to regret the lack of the "saving common-sense" possessed by many far less gifted men. His erudition and insight are always a little in advance of his good judgment. As to the works of the first class, the _Reminiscences_ are defaced by the shrewish spirit shown in the accounts of Wordsworth and other friends; nor can we depend upon them as records of fact. But our author had had exceptional opportunities to observe these famous men and women, and he possessed no little insight into literature and personality. As to the _Autobiographic Sketches_, the handling of events is hopelessly arbitrary and fragmentary. In truth, De Quincey is drawing an idealized picture of childhood,--creating a type rather than re-creating a person; it is a study of a child of talent that we receive from him, and as such these sketches form one of the most satisfactory products of his pen.