RECENT ADVANCES IN SCIENCE BEARING ON MEDICINE. 573 



matter depends. How great was the step from Paracelsus to Glisson 

 and, we may continue, from Glisson to Hunter! According to Para- 

 celsus, life was the work of a special spiritus, which set material sub- 

 stance in action, like a machine; for Glisson, matter itself was the 

 principium energeticum. Unfortunately, he did not confine this dictum 

 to living substances only, but applied it to substance in general, to all 

 matter. It was Hunter who first announced the specific nature of liv- 

 ing matter as contrasted with nonliving, and he was led to place a 

 materia vitce diffusa at the head of his physiological and pathological 

 views. According to the teaching of Hewson and Hunter, the blood 

 supplied the plastic materials of physiology as well as the plastic 

 exudates of pathology. Such was the basis of the new biological 

 method, if one can apply such an expression to a still incomplete 

 doctrine, in 1842, when Huxley was beginning his medical studies at 

 Charing Cross Hospital. It would lead too far afield were I to recount 

 in this place how it happened that I myself, like Huxley, was early 

 weaned from the pernicious doctrines of humoral pathology. 



THE DEVELOPMENT OF BIOLOGY. 



When Huxley himself left Charing Cross Hospital, in 1846, he had 

 enjoyed a rich measure of instruction in anatomy and physiology. 

 Thus trained, he took the post of naval surgeon, and by the time that 

 he returned, four years later, he had become a perfect zoologist and a 

 keen-sighted ethnologist. How this was possible anyone will readily 

 understand who knows from his own experience how great the value 

 of personal observation is for the development of independent and 

 unprejudiced thought. For a young man who, besides collecting a 

 rich treasure of positive knowledge, has practiced dissection and the 

 exercise of a critical judgment, a long sea voyage and a peaceful sojourn 

 among entirely new surroundings afford an invaluable opportunity for 

 original work and deep reflection. Freed from the formalism of the 

 schools, thrown upon the use of his own intellect, compelled to test 

 each single object as regards properties and history, he soon forgets 

 the dogmas of the prevailing system and becomes first a skeptic and 

 then an investigator. This change, which did not fail to affect Huxley, 

 and through which arose that Huxley whom we commemorate to-day, 

 is no unknown occurrence to one who is acquainted with the history 

 not only of knowledge, but also of scholars. We need only to point to 

 John Hunter and Darwin as closely allied examples. The path on 

 which these men have achieved their triumphs is that which biology in 

 general has trodden with ever- widening strides since the end of last 

 century — it is the path of genetic investigation. We Germans point 

 with pride to our countryman who opened up this road with full con- 

 viction of its importance, and who directed toward it the eyes of the 

 world — our poet-prince Goethe. What he accomplished in particular 



