Thus, when we read the description of some picturesque scene in nature, the mind immediately groups together mountains, trees, brooks, cottages, and glens, forming a new combination of conceptions different from any scene we ever witnessed or conceived before. All the objects thus combined are conceptions; the act of arranging them is an act of the imagination. _Judgment_ is the power which the mind possesses of _noticing relations_. A _relation_ is an idea obtained by observing one thing in connection with another. Thus, when we perceive one thing to be _longer_ than another, one thing to be _on_ another, or one thing to _belong_ to another--in all these cases the mind _notices relations_, or exercises the faculty of judgment. Thus, also, when we compare any action with the rule of duty in order to decide whether it is right or wrong, we exercise the same faculty. This act always is necessarily preceded by the comparison of one thing with another, in order to notice the relations. _Abstraction_ is the power of noticing certain parts or qualities of any object, as distinct from other parts or qualities. Thus, when we notice the length of a bridge without attending to the breadth or color, or when we notice the height of a man without thinking of his character, we exercise the faculty of abstraction. _Attention_ is the direction of the mind to any particular object or quality, from the interest which is felt in it, or in something connected with it. The degree of attention is always proportioned to the degree of interest felt in the object. _Association_ is the power possessed by the mind of recalling ideas in the connections and relations in which they have existed in past experience. For example, when any two objects, such as a house and a tree, have often been observed together, the idea of one will ordinarily be attended by that of the other. If two events have often been united together in regard to the _time_ of their occurrence, such, for example, as thunder and lightning, the idea of one will usually be attended by the other. In this work, the aim is to introduce no more of mental analysis than is needed for its main object. What is here introduced is not claimed as a complete presentation of all the mental phenomena. CHAPTER IX. SENSATION AND PERCEPTION. As there is no distinction between sensation and perception except in the fact that one is attended with the belief of a cause and the other is not, they will be treated of together. The mind of man is an immaterial existence, confined in its operations by the body it inhabits, and depending upon the construction and modifications of this envelope for much of its happiness or suffering.