Enough has been said to give you some insight into the facilities with which your new employment abounds. I will only mention one more, because of its extensive and almost universal application to all Branches of Literature; the topic, I mean, which by the old Rhetoricians was called ἐξ ἐναντίων, That is, when a Work excels in one quality; you may blame it for not having the opposite.
For instance, if the biographical sketch of a Literary Character is minute and full of anecdote; you may enlarge on the advantages of philosophical reflection, and the superior mind required to give a judicious analysis of the Opinions and Works of deceased Authors. On the contrary, if the latter method is pursued by the Biographer; you can, with equal ease, extol the lively colouring, and truth, and interest, of exact delineation and detail.
This topic, you will perceive, enters into Style as well as Matter; where many virtues might be named which are incompatible: and whichever the Author has preferred, it will be the signal for you to launch forth on the praises of its opposite; and continually to hold up that to your Reader as the model of excellence in this species of Writing.
You will perhaps wonder why all my instructions are pointed towards the Censure, and not the Praise, of Books; but many reasons might be given why it should be so. The chief are, that this part is both easier, and will sell better.
Let us hear the words of Mr Burke on a subject not very dissimilar:
"In such cases," says he, "the Writer has a certain fire and alacrity inspired into him by a consciousness that (let it fare how it will with the subject) his ingenuity will be sure of applause: and this alacrity becomes much greater, if he acts upon the offensive; by the impetuosity that always accompanies an attack, and the unfortunate propensity which mankind have to finding and exaggerating faults." Pref., Vindic. Nat. Soc., p. 6.