156 PSYCHOLOGY. 



Wlietlier these local contrasts shade into each other 

 ■with absolutely continuous gradations, we cannot say. But 

 we know (continues Wiindt) that 



*' they change, when we pass from one point of the skin to its neigh- 

 bor, with very different degrees of rapidity. On delicately-feeling 

 parts, used principally for touching, such as the finger-tips, the dif- 

 ference of sensation between two closely approximate points is already 

 strongly pronounced ; whilst in parts of lesser delicacy, as the arm, the 

 back, the legs, the disparities of sensation are observable only between 

 distant spots." 



The internal organs, too, have their specific qualia of sen- 

 sation. An inflammation of the kidney is different from 

 one of the liver ; pains in joints and muscular insertions 

 are distinguished. Pain in the dental nerves is wholly 

 unlike the pain of a burn. But very imj)ortant and curious 

 similarities prevail throughout these differences. Internal 

 pains, whose seat we cannot see, and have no means of 

 knowing unless the character of the jDain itself reveal it, 

 are felt ivhere they belong. Diseases of the stomach, 

 kidney, liver, rectum, j)rostate, etc., of the bones, of the 

 brain and its membranes, are referred to their proper posi- 

 tion. Nerve-pains describe the length of the nerve. Such 

 localizations as those of vertical, frontal, or occipital head- 

 ache of intracranial origin force us to conclude that j)arts 

 which are neighbors, whether inner or outer, may possess 

 by mere virtue of that fact a common peculiarity of feeling, 

 a respect in which their sensations agree, and which serves 

 as a token of their j)roximity. These local colorings are, 

 moreover, so strong that we cognize them as the same, 

 throughout all contrasts of sensible quality in the accom- 

 panying perception. Cold and heat are wide as the poles 

 asunder ; yet if both fall on the cheek, there mixes with 

 them something that makes them in that respect identical ; 

 just as, contrariwise, despite the identity of cold with itself 

 wherever found, when we get it first on the palm and then 

 on the cheek, some difference comes, which keeps the two 

 experiences for ever asunder.* 



* Of the anatomical and physiological conditioDS of these facts we know 

 as yet but little, and that little need not here be discussed. Two principal 

 hypotheses have been invoked in the case of the retina. Wundt {Men- 



