IMPROVISATION. poorer classes. Improvi^-ution is by no means limited to brief poems of n few verses, and of >iiiiplf structiirf, but is often oarrii-d on in com- plicated metres, and to great length. Some of (lie most famous of the Italian ituprnvisatori have been: the Venetian I.*oniceno (died 1524) ; Serafino of Aquila (died 1500) : Accolti of Arez- zo (sixteenth century I; .Mclastasio (q.v. ), who, lunvi'Ver, soon abandoned the art; and Tommaso Syrici (died 183ti). In Corsica and Sardinia there are many women (improvisat rices) who im- provise loll".' memorial poems at funerals. Among the best-known improvisalrices may be mentioned -Mapdalena Fernandez (died 1800), Signora Maz- zei (born c.1800) ; and tiiovannina Milli. In music, improvisation is the art of perform- ing e.temporaneously upon an instrument. A given theme or themes may be developed in strict form, or the performer may give himself up to momentary impulses and employ any number of themes in a free fanta.-ia. The former, however, is a great art, and nearly all the masters, notably Uach and Heethoven, excelled in it. To im- provise in a given form requires not only an un- u>ual conuiiand over the technique, but also a marvelous power of conc-entration. Undoubtedly the improvisation of a strict fugue is the most ditlicult task imaginable. Bach was a master of this. IMPULSE (from Lat. impulsus, incitement, from impellerc, to incite, from in. in -f pellere, to drive). The typical motive to voluntary ac- tion. (See Action.) Such action is, at first, unequivocally determined: that is to say, the bo<lily movement follows, without hesitation or rellection, upon the fonnation of single, unchal- Itnged motive. As the physical organism and the r.iind grow in complexity, voluntarj' action comes to be equivocally conditioned: there is a period of deliberation and doubt, characterized by a con- flict of motives, some one of which ultimately prevails, as actual motive, over the potential motives, its rivals. The simplest form of voluntary action, that which is prompted unequivocally by one unques- tioned motive, is termed in psychology impul- sive action, and the motive itself an impulse. The scientific definition of the terms is reflected in popular usage: we call a character 'impulsive' which acts off-hand, without balancing of alterna- tive? : though the ideas of wapvardness and unaccountability that we associate with the idea of an "impulsive character' do not attach to the impulse as such, but indicate rather some in- heiited idiosyncrasy or defect of early training. The impulse proves, on analysis, to be a fairly stable connection of sensational and affective proc- esses. If we look at it in its complete or perfect form, but make its constituent processes as simple as possible, we find the following com- ponents: (I) the perception of an object to ■which we are attracted or from which we are re- pelled; (2) an idea of our own movement to- ward or away from the object, based upon pre- vious experience of actual movements: (,"?) an idea of the result of oir movement; and (4) an afTective process, the resultant of the affective colorings — oftentimes mutually opposed — of the three sensorj- factors. It is not difficult, in laboratory practice, to arrange for the formation of a motive in which these latter processes shall be represented on practically equal terms. In 508 IMPUTATION. real life, although (as we said) the impulse is fairly stable in composition, we usually find a predominance of some one of the three ideas, and a subordination of the others. Thus, the idea of our own movement may recede far into the back- giound of the impulsive consciousness, where it finds expression, perhaps, only in some incon- spicuous fringe of organic sensation ; while, as the reach of consciousness increases, the idea of object comes more and more to be lost sight of in comparison willi the idea of end or result. It should l>e remarked, further, that the idea of our own movement, important as it is at a cer- tain level of mental development, cannot be con- tained in the verj' first impulse, and cannot be of niuch importance for a considerable time after voluntary movements have been initiated: for, on the one hand, we nmst have moved before we can have an idea of our movement (so that the most primitive action of all is an 'action upon presentation,' made in response to the simple [X'rception of object) ; and, on the other, primi- tive movements are too vague, and too little dif- ferentiated, to play the regulating and refining part that they later assume. Conversely, the complex motives that enter into conlliet with one another in volitional and selective actiim are simply complicated impulses, in which the place of perception and idea is taken by associations of ideas or by judgments or trains of reasoning. It is dilficult to give an illustration of an im- pulsive action, for the reason that what is im- pulsive in one man's consciousness need not be so in another's. The impulsive action which we select may have been repeated so often as to have degenerated into ideomotor action, or even into a secondary reflex; or it may be so unaccustomed as rather to deserve the name of selective or volitional action. We can, however, take a fictitious case. Suppose that a boating party, arriving at a secluded bay, are seized with the impulse to bathe. Here we have the object-per- ception of the cool, clear water; the anticipation in idea of the free movements of diving and swimming; and the further forecast of the bodily vigor and refreshment that will ensue. All three ideas are pleasant. An opposition of affective processes might arise if the water is distinctly cold: in this case, the combined pleasantness of movement and result overcome the unpleasant- ness of the object-perception. It is, however, easy to .see that, for persons who always bathed when they had the opportunity, the action would be rather ideomotor than impulsive; whereas, by those members of the party who were weak swim- mers, the phmge might be taken only after a good deal of hesitancy and indecision. BlBLloGRAPnY. Wundt, GrundzUfje drr phy- siologinchcn Psi/chologie (Leipzig, 1803) ; id., I.cclures on Human and Animal Psticholoflx) (New York, 189G) ; Schneider, Der tierische Wille (Leipzig, 1880) : id., Drr mcnschlichc Wille (Berlin, I88'2) ; Titchcner, Outline of Pnycholopi/ (Xew York, 1899) ; Sully, Human Mind (Lon- don, 1892) ; Preyer, Die Seele des Kindes (Leip- zig, 1990). IMPULSE OF A FOBCE. See JIechanics. IMPUTATION (T,at. impuiatio. from impu- tarc. to ascribe, from in. in + putare, to think, from puius. clear; connected with Lat. purus, pure, Skt. pu. to purify). One of the common technical terms of Christian theology. It de-
