12. According to the most elementary rules of logic, it is necessary to
understand a question before discussing it for the critic's verdict is of no value unless
founded on a complete knowledge of his subject ; in that case, and in that alone, his
opinion, even if erroneous, may be worthy of consideration but what is it worth in a
matter of which he is ignorant ? The true critic should give proof, not only of erudition,
but of thorough knowledge of the subject of which he treats, of sound judgement, and
unquestionable impartiality ; otherwise we might as 'veil be guided by the opinion of
the first organ-grinder we meet with who should take upon himself to criticise Rossini,
or that of any mere copyist who might think fit to censure Raphael.
