i8 95 . SOME NEW BOOKS. 55 



Two Books on Psychology. 



Lectures on Human and Animal Psychology. By Wilhelm Wundt. Translated 

 from the Second German Edition by J. E. Creighton and E. B. Titchener. 

 Pp. x. and 454. Illustrated. London : Swan Sonnenschein & Co., 1894. Price 15s. 



Introduction to Comparative Psychology. By C. Lloyd Morgan. With 

 diagrams. Pp. vii. and 382. London : Walter Scott, 1894. Price 6s. 



Even in our own country, so agape for mesmeric marvels, so inapt 

 at intellectual novelties, there is evidence that psychology on its 

 scientific or physiological side is receiving a considerable amount of 

 attention. Of the two books before us the second or smaller is a 

 purely English production. The translation of Wundt's lectures is 

 an English issue of an American book. 



As Sachs is to Botany, so is Wundt to Psychology. As Wundt 

 says in the preface to the second edition of his lectures, " Thirty 

 years ago the science was no more than a programme for the future." 

 Fechner had begun to break the ground in psychophysics, but other- 

 wise everything remained to be done. Psychology, so-called, was in 

 the hands of dogmatists and metaphysicians. The application of the 

 exact methods of an extended physiology to the senses and the mind 

 met with distrust on all hands. Memories of the degradation of what 

 was regarded as psychology in these days still linger in this country in 

 association with the phrase " Psychological novel." Consider what 

 is implied by calling " Une Cruelle Enigme " or " The Yellow Aster " 

 psychological novels, as our esteemed literary contemporaries delight 

 to do, and you shall know what psychology was when, thirty years ago, 

 the first edition of these lectures was published. The means by which 

 Wundt and his pupils have made psychology an exact science are 

 simple ; they are experiment and observation. In place of subjective 

 analysis in these lectures we have the record of the subjection of vision 

 and touch and hearing, memory and attention to a rigorous experi- 

 mental method. 



A comparison of the method of Wundt with that of Dr. Bain, 

 the most physiological of the older school of psychologists, will make 

 the change of attitude more apparent. Bain introduced his account 

 of the great law of relativity by general considerations, like our 

 knowledge of heat as an appreciation of a transition from cold, by 

 a comparison of the contrast between health and sickness, leisure 

 and toil, and so forth. Wundt starts from actual experiments on 

 sensation-differences and associates definitely with the law of 

 relativity the idea of quantitative apprehension of contrast. Bain 

 describes anatomical structures, introduces physiological conceptions 

 and correlates them with sensations, but does not embark upon the 

 measuring of sensations at all. Wundt, at the outset, begins with 

 the idea of units of sensation and of sensation-stimuli, to be fixed by 

 definite experiment, and to be used as the bases of all future 

 experiment. Thus, in the case of sound-stimuli, it can be shown 

 that a normally sensitive ear can just hear the sound made by a 

 pellet of cork weighing one milligramme falling through a height of 

 one millimetre upon a sheet of glass, at a distance of ninety-one milli- 

 metres from the ear. " Given a sound, the intensity of which it is 

 desired to measure, it is only necessary to remove it to the distance 

 at which it just disappears." As a sensation-stimulus it then pre- 

 cisely equals the unit, it produces the just-noticeable sensation, and 

 the distance tells us how much greater is the given sound at the 

 place of its production than is the just-noticeable sound intensity. 



