"Definitions," says Duncan, in his Elements of Logic, "are intended to make known the meaning of words standing for _complex ideas_;[65] and were we always careful to form those ideas exactly in our minds, and copy our definitions from that appearance, much of the confusion and obscurity complained of in languages might be prevented."-- P.

70.

Again he says: "The writings of the mathematicians are a clear proof, how much the advancement of human knowledge depends upon a right use of definitions."-- P.

72.
Mathematical science has been supposed to be, in its own nature, that which is best calculated to develop and strengthen the reasoning faculty; but, as speech is emphatically _the discourse of reason_, I am persuaded, that had the grammarians been equally clear and logical in their instructions, their science would never have been accounted inferior in this respect.

Grammar is perhaps the most comprehensive of all studies; but it is chiefly owing to the unskillfulness of instructors, and to the errors and defects of the systems in use, that it is commonly regarded as the most dry and difficult.
5.