§ 49. =The Nature of Emotion.=—Suppose that you are sitting at your desk, busy in your regular way; and suppose that a street-car passes by the house. The familiar rumble does not distract you; it slips in among the obscure processes of the margin. Suddenly you hear a shrill scream; and now the noise of the car shoots to the focus of attention, becomes the context of the scream. You leap up, as if the scream were a personal signal that you had been expecting; you dash out of doors, as if your presence on the street were imperatively necessary. As you run, you have fragmentary ideas: ‘a child,’ perhaps, in internal speech; a visual flash of some previous accident; a momentary kinæsthetic set, the stiffening of protest, that represents your whole attitude to the city car-system. But you have, also, a mass of insistent organic sensation: you choke, you draw your breath in gasps, for all the hurry you are in a cold sweat, you have a horrible nausea; and yet, in spite of the intense discomfort that floods you, you have no choice but to go on. In describing the experience later, you would say that you were horrified by hearing a child scream; the mental processes that we have just named make up the =emotion= of horror. An emotion is thus a _temporal_ experience, a course of connected processes; it begins, in our illustration, with the empathic perception of the scream, and lasts through and beyond the events that we have described; indeed, the last traces of the horror may not wear off for days. It is also, characteristically, a _suddenly aroused_ experience; it begins abruptly, though it dies down gradually; the accident comes upon you all at once, and drives everything else out of mind. It is highly _complex_, since its stimulus is not a single object, a perceptive stimulus, but a total situation or predicament, which may arouse all sorts of ideas. It is coloured through and through by _feeling_, since both the situation itself and the organic sensations of the emotive response are definitely pleasant or unpleasant. It is, at any rate in its more intense phases, insistently _organic_; we took the testimony of language on p. 65, and you can easily add to the instances there cited; though it must be said also that the proportion of organic sensations to ideas varies greatly from emotion to emotion and from individual to individual. Finally, it is always a _predetermined_ experience, issuing from determining tendencies and moving forward, in the given case, to a natural end; though here, too, there is great variability, since the determining tendencies to which the situation makes appeal may be almost wholly instinctive, or may (as in the illustration we have chosen) be partly instinctive and partly acquired.