=Disposition.=--A particular kind of mood frequently indulged in produces a type of emotional habit, our _disposition_. For instance, the teacher who permits the occurrences of the class-room to trouble him unnecessarily, and who broods over these afterwards, soon develops a worrying disposition. As we have it in our power to determine what habits, emotional and otherwise, we form, we alone are responsible for the dispositions we cultivate. =Temperament.=--Some of us are provided with nervous systems that are predisposed to particular moods. This predisposition, together with frequent indulgence in particular types of mood, gives us our _temperament_. The responsibility for this we share with our ancestors, but, even though predisposed through heredity to unfortunate moods, we can ourselves decide whether we shall give way to them. Temperaments have been classified as _sanguine_, _melancholic_, _choleric_, and _phlegmatic_. The sanguine type is inclined to look on the bright side of things, to be optimistic; the melancholic tends to moodiness and gloom; the choleric is easily irritated, quick to anger; the phlegmatic is not easily aroused to emotion, is cold and sluggish. An individual seldom belongs exclusively to one type. =Sentiments.=--Certain emotional tendencies become organized about an object and constitute a _sentiment_. The sentiment of love for our mother had its basis in our childhood in the perception of her as the source of numberless experiences involving pleasant feeling tones. As we grew older, we understood better her solicitude for our welfare and her sacrifices for our sake--further experiences involving a large feeling element. Thus there grew up about our mother an organized system of emotional tendencies, our sentiment of filial love. Such sentiments as patriotism, religious faith, selfishness, sympathy, arise and develop in the same way. Compared with moods, sentiments are more permanent in character and involve more complex knowledge elements. Moreover, they do not depend upon physiological conditions as do moods. One's organic sensations may affect one's mood to a considerable extent, but will scarcely influence one's patriotism or filial love. CHAPTER XXX THE WILL VOLUNTARY CONTROL OF ACTION