It would seem rather superfluous to remark, that no science can be definite or precise, whose terms are undefined and inexact, and that it behoves the student in any science, to understand the terms employed, before he can master his subject; more especially is this the case, where the subject treats of abstract qualities and ideas, whose fundamental terms, themselves expressing abstracts, require defining from the very beginning: and yet, the difficulty I have met with, and which others have experienced in those terms which form the subject of the following remarks, will perhaps shew that such precision is not so universally observed as is supposed.