_The true Nature of Abstraction._--But suppose now that instead of thinking of the redness of this rose in particular, I think of the color red in general, without reference to the rose or any other substance; or, to carry the process further, of color in general, without specifying in my thought any particular color, evidently I am dealing now with abstractions. I have in my thought _drawn away_ (abstraho) the color from the substance to which it belongs, from all substance, and it stands forth by itself a pure conception, an _abstraction_, having, as such, no existence save in my mind, but there it does exist a definite object of contemplation. The form of mental activity now described, I should call _abstraction_. It is not necessary, perhaps, to assign it a place as a distinct faculty of the mind. It is, in reality, a part, and an important part, of the synthetic process already described. But it is not the whole of that process, and the term abstraction should not, therefore, in strict propriety, at least as now defined, be applied as a general term to designate that class of mental operations. The synthetic process involves something more than mere abstraction; viz.: II. CLASSIFICATION AS DISTINGUISHED FROM GENERALIZATION. _Classification._--When the general idea or conception has been formed in the mind, we proceed to bring together and arrange, on the basis of that general conception, whatever individual objects seem to us to fall under that general rule. This we call classification. Thus, forming first the abstract, or general conception red, we bring together in our thought a variety of objects to which this conception is applicable, as red horses, red flowers, red books, red tables, etc., etc., thus forming classes of objects on the ground of this common property. The difference between _classification_ and _generalization_, in so far as they are not synonymous, I take to be simply this, that in the former we group and arrange objects according to no general law, but mere appearance or resemblance, often, therefore, on fanciful or arbitrary grounds while in the latter case, we proceed according to some general and scientific principle or law of classification, making only those distinctions the basis of our arrangement which are founded in nature, and are at once invariable and essential. III. JUDGMENT AS RELATED TO CLASSIFICATION.