In the preceding chapters, we have apparently neglected a large and important class of content, and the reaction processes through which it is perceived. Sentienda and relations make up the outer world: but there is an inner world of feeling which is just as real as the outer world, and in some respects more important. What is this inner world, and how do we experience it? The answering of this question can be delayed no longer.
Under the general names of "feelings and emotions" we customarily include such things as joy, rage, melancholy, pain, hunger, fatigue, thirst, amourousness, irritation, pleasure, desire, and sometimes even such obviously sensory contents as tickle, warmth and touch. The apparent nondescriptness of this group of things has led to a distinction being raised between the obvious sentienda included in the group, and those things which are less obviously sentienda, and the application of the terms affections, affects or affective contents to the latter. Whether this distinction is useful or harmful will be considered later.
Among the affective contents, it has been the custom of psychologists to distinguish the simpler affects from the more complex, and to apply the term feelings to the former, and the term emotions to the latter. In popular usage, however, although the term "emotion" has been restricted as among psychologists, the term "feeling" has been applied to the whole group. There seems to be no use in attempting to oppose popular usage on this point, and we shall therefore follow it.
Feelings are actual data in experience. They are facts, not inferences; and they are content of which we are aware. They are comparable to sentienda, in that they have intensity, duration, and sometimes even extensity, and are spatial to the extent of