MODERN BIOLOGY 383 



and ends with exact research, first physiological and then comparative 

 anatomical. From childhood Miiller possessed a mobile and imaginative 

 temperament; he had a tendency to hallucinations, which he later on studied 

 from a scientific point of view, and the education he received at Bonn was 

 well adapted to develop this over-imaginative side of him. Among his 

 tutors, it is worth noting, were Nees von Esenbeck, the fantastic botanist, 

 who has previously been described, and the Schellingian Brandis. His dis- 

 sertation for his doctor's degree. On the Relations of Numbers in connexion with 

 the Movements of Animals, is also entirely in the spirit of Oken;' here one may 

 read, amongst other things, that "bending and stretching are the two poles 

 of life, the former resembling the closed bud, the latter the opened but with- 

 ered flower; in both night prevails, but between them moves life." In his 

 old age Miiller is said to have destroyed all the copies of this fantastic pro- 

 duction that he could lay hands on. His visit to Rudolphi distinctly cooled 

 his ardour for extravaganzas of this sort, while the reading of Berzelius is 

 said to have had an even deeper influence upon him in this respect. Before 

 he entirely abandoned the natural-philosophical school, however, Miiller 

 published his investigations into subjective sense-perceptions, which were 

 undoubtedly the finest work on natural science produced by German ro- 

 mantic philosophy. Like Purkinje, who in this subject was his predecessor, 

 Miiller takes as his starting-point Goethe's colour-theory. The physical 

 qualities of light do not interest him at all and he accepts the theory of 

 light's "primal phenomena (Urphanomeny although he is not blind to its 

 weaknesses; what attracted him to Goethe is the latter 's observations on the 

 subjectivity of the sense-perceptions; taking these as his starting-point, 

 Miiller builds up with ample material derived from personal observations 

 his general theory of the specific forms of energy of the sensory organs. He 

 establishes the fact that every sensory organ reacts in its own special way 

 towards every kind of irritation; for instance, the eye through light-impres- 

 sions reacts just as much to blows and electric current as to daylight; on the 

 other hand, different organs of sense react each in its own way to the same 

 irritation; thus, to irritation caused by electricity the eye responds through 

 light-impressions, the ear through sound, the tongue through taste; and 

 finally each sensory organ can express its individual reaction to impressions 

 from within, in which are produced "imaginary sense-phenomena," or what 

 would nowadays be called hallucinations. Through these facts Miiller has 

 laid the foundations of experimental sense-physiology, which has been so 

 diligently studied in modern times; thanks to his extraordinary powers of 

 observation and clearness of thought, he succeeded in doing so in spite of 

 the natural-philosophical principles on which his research was based. We 



^ A German resume of this work is included in the 1812. number of Oken's Ish. 



