It appears to us especially well suited to the wants of the age, to the hurried moments which it can consecrate to study.
A treatise has, doubtless, an incontestable superiority; but upon condition that it be read, meditated upon, searched into.

It addresses itself to a select public only.

Its mission is, at first, to fix, and afterwards to enlarge, the circle of acquired knowledge.
The refutation of vulgar prejudices could not carry with it this high bearing.

It aspires only to disencumber the route before the march of truth, to prepare the mind, to reform public opinion, to blunt dangerous tools in improper hands.

It is in social economy above all, that these hand-to-hand struggles, these constantly recurring combats with popular errors, have a true practical utility.
We might arrange the sciences under two classes.