He alone can know whether his predecessors went right or wrong, who is capable of a judgement independent of theirs.

But with what shameful servility have many false or faulty definitions and rules been copied and copied from one grammar to another, as if authority had canonized their errors, or none had eyes to see them! Whatsoever is dignified and fair, is also modest and reasonable; but modesty does not consist in having no opinion of one's own, nor reason in following with blind partiality the footsteps of others.
Grammar unsupported by authority, is indeed mere fiction.

But what apology is this, for that authorship which has produced so many grammars without originality?
Shall he who cannot write for himself, improve upon him who can?
Shall he who cannot paint, retouch the canvass of Guido?
Shall modest ingenuity be allowed only to imitators and to thieves?
How many a prefatory argument issues virtually in this! It is not deference to merit, but impudent pretence, practising on the credulity of ignorance! Commonness alone exempts it from scrutiny, and the success it has, is but the wages of its own worthlessness! To read and be informed, is to make a proper use of books for the advancement of learning; but to assume to be an author by editing mere commonplaces and stolen criticisms, is equally beneath the ambition of a scholar and the honesty of a man.
"'T is true, the ancients we may rob with ease; But who with that mean shift himself can please ?" _Sheffield, Duke of Buckingham_.
7.

Grammar being a practical art, with the principles of which every intelligent person is more or less acquainted, it might be expected that a book written professedly on the subject, should exhibit some evidence of its author's skill.

But it would seem that a multitude of bad or indifferent writers have judged themselves qualified to teach the art of speaking and writing well; so that correctness of language and neatness of style are as rarely to be found in grammars as in other books.