I. _Abstraction_, by which is meant the process of _drawing off_ and _setting aside_ from an object, person or thing, _a quality or attribute_, and making of it a distinct object of thought. For instance, if I perceive in a _lion_ the quality of _strength_, and am able to think of this quality abstractly and independently of the animal--if the term _strength_ has an actual mental meaning to me, independent of the lion--then I have _abstracted_ that quality; the thinking thereof is an act of _abstraction_; and the thought-idea itself is an _abstract idea_. Some writers hold that these abstract ideas are realities, and "not mere figments of fancy." As Brooks says: "The rose dies, but my idea of its color and fragrance remains." Other authorities regard Abstraction as but an act of _attention_ concentrated upon but the particular quality to the exclusion of others, and that the abstract idea has no existence apart from the general idea of the object in which it is included. Sir William Hamilton says: "We can rivet our attention on some particular mode of a thing, as its smell, its color, its figure, its size, etc., and abstract it from the others. This may be called Modal Abstraction. The abstraction we have now been considering is performed on individual objects, and is consequently particular. There is nothing necessarily connected with generalization in abstraction; generalization is indeed dependent on abstraction, which it supposes; but abstraction does not involve generalization." II. _Generalization_, by which is meant the process of forming Concepts or General Ideas. It acts in the direction of apprehending the common qualities of objects, persons and things, and combining and uniting them into a single notion or _conception_ which will comprehend and include them all. A General Idea or Concept differs from a particular idea in that it includes within itself the qualities of the particular and other particulars, and accordingly may be applied to any one of these particulars as well as to the general _class_. For instance, one may have a _particular idea_ of some _particular_ horse, which applies only to that particular horse. He may also have a General Idea of _horse_, in the generic or _class_ sense, which idea applies not only to the general class of _horse_ but also to each and every _horse_ which is included in that class. _The expression of Generalization or Conception is called a Concept._ III. _Judgment_, by which is meant the process of comparing two objects, persons or things, one with another, and thus perceiving their agreement or disagreement. Thus we may compare the two concepts _horse_ and _animal_, and perceiving a certain agreement between them we form the judgment that: "A _horse_ is an _animal_;" or comparing _horse_ and _cow_, and perceiving their disagreement, we form the judgment: "A _horse_ is not a _cow_." _The expression of a judgment is called a Proposition._