Most of the consideration about the functioning of the human mind addresses intellect and reason - but in fact the greater part of mental activities are concerned with feeling and emotion. In Atkinson's time, emotion and thought were assumed to exist in different parts of the mind, and emotion was considered to be a more primitive and stronger influence than reason, which was "the youngest child of the mind.:"
Atkinson differentiates feeling and emotion much in the same way as sensation and perception: a feeling comes upon us, and we have an emotional reaction to it. He also confides feeling to be an "agreeable or disagreeable mental state" that is quite binary in its nature, and only when it has been evaluated and associated to memory that it becomes a more specific emotion.
He acknowledges the term is used vaguely and incorrectly in casual conversation: we say that a person "feels sad" or has "feels interested" or has "a feeling of triumph" when none of these are actual feelings, but emotional or rational evaluations of a mental state.
He does consider that in addition to its polarity, feeling is also characterized by intensity - just as the body senses a strong or mild feeling of pressure on the skin, so does the mind sense a strong or weak level of a feeling state.
There is also the distinction between feeling and sensation, in that sensation refers to data received from the outside world whereas feelings are internal. The same temperature sensed by two different people gives one a positive feeling (refreshingly cool) and another a negative feeling (unpleasantly cold) - so the sensations pertain to what is perceived from outside the mind and the feelings are reactions to those sensations.
Not every sensation evokes a feeling, as we are neutral to many events. If you accidentally drop something and recognize that it was not damaged, you pick it up immediately without any reaction. If you suspect that it might be damaged, there is a fleeting negative feeling that lasts only until you recognize that it has not been damaged.
Positive and negative feelings have also been equated with pain or pleasure, and they are customarily but not always so. Pain and pleasure are a prolonged state, whereas feeling is brief and ceases very soon after the initial sensation is no longer in effect. Much of what we consider pain and pleasure are emotional or intellectual states rather than feelings. It also becomes clear that they are different when you consider that overindulgence in pleasurable activities turns the sensation into pain.
Atkinson also suggests that feelings may be classified according to their source: some arise from physical sensations and others arise from ideas. Simply imagining something can cause a person to experience positive or negative feelings.
It is also suggested that feelings may exist in animals. While it is common to anthropomorphize a pet as having emotions, it is incapable of them - but it may be capable of having feelings and expressing a reaction to them. It is suspected that many of the emotional states of man may have evolved from feelings or primitive proto-emotions in animals.
(EN: I'm skipping the remainder of the chapter because it blurs the lines between a feeling, and emotion, and a thought in terms of the author's own descriptions. Not only is the consideration of feelings outdated, but it is also self-contradictory.)