colours, for example, which may not be pure sensations, but a sort of intermediate affections; yet when we consider it strictly, red, and the others, means nothing more than what produces in me a certain sensation of sight. This leads me to understand how it is that I attain to a knowledge of things out of myself. I am affected in a particular manner—this I know absolutely;—this affection must have a foundation; this foundation is not in myself, and therefore must be out of myself;—thus I reason rapidly and unconsciously, and forthwith assume the existence of such a foundation, namely, the object. This foundation must be one by which the particular affection in question may be explained;—I am affected in the manner which I call a sweet taste, the object must therefore be of a kind to excite a sweet taste, or more briefly, must itself be sweet. In this way I determine the character of the object.
Spirit. There may be some truth in what thou sayest, although it is not the whole truth which might be said upon the subject. How this stands we shall undoubtedly discover in due time. Since, however, it cannot be denied that in other cases thou dost discover some truth by means of this principle of causality,—so I term the doctrine which thou hast just asserted, that everything (in this case thy affection) must have a foundation or cause,—since this, I say, cannot be denied, it may not be superfluous to learn strictly to understand this procedure, and to make it perfectly clear to ourselves what it is thou really dost when thou adoptest it. Let us suppose, in the meantime, that thy statement is perfectly correct, that it is by an unconscious act of reasoning, from the effect to the cause,
