LUCRETIUS AND HAECKEL 1 33 



Haeckel: "Pathological experiment yields the same result, the 

 decay of some known area (for instance, the center of speech) extin- 

 guishes its function (speech). In fact, there is proof enough in the 

 most famiUar phenomena of consciousness of their complete depend- 

 ence on chemical changes in the substance of the brain. Many bever- 

 ages (such as coffee and tea) stimulate our powers of thought; others 

 (such as wine and beer) intensify feehng; musk and camphor reani- 

 mate the fainting consciousness; ether and chloroform deaden it, 

 and so forth. How would that be possible if consciousness were 

 an immaterial entity, independent of these anatomical organs ? And 

 what becomes of the consciousness of the 'immortal soul' when it no 

 longer has the use of these organs?'" 



Naturally we do not expect to find in Lucretius any histological 

 argument, ''based on the extremely complicated microscopic structure 

 of the brain," nor a phylogenetic argument, "deriving its strength 

 from paleontology, and the comparative anatomy and physiology 

 of the brain," nor any strictly experimental argument as to areas of 

 function; but it is safe to say that not a single reader who fails to be 

 convinced by Haeckel's other arguments would be moved by the three 

 enumerated in this sentence, e. g., by the "quantitative and quaU- 

 tative development of the brain of the placental mammals during the 

 tertiary period."^ 



It would seem to me also safe to say that not a single reader who 

 would fail to be converted by the De Rerum Natura would be seriously 

 moved by the Weltrdthsel. Of course, the latter marshals all the argu- 

 mentative panoply of our wonderful modern science, with its count- 

 less facts and illuminating theories, and the mere enumeration of the 

 arguments given above suggests the arms that a modern monist may 

 take into his hands; but the new arms, it seems to me, would reach 



' WR., 184. Of course, the localization of the organs of thought in the modern sense is entirely unknown 

 to Lucretius, so that his arguments are naturally drawn from "the most familiar phenomena of conscious- 

 ness. " He actually thought of the breast as the central seat of consciousness with the vital principle extending 

 through every part of the body. "Now I assert that the mind and soul are kept together in close imion and 

 make up a single nature, but that the directing principle which we call mind and understanding, is the head, 

 so to speak, and reigns paramount in the whole body. It has a fixed seat in the middle region of the breast; 

 here throb fear and apprehension, about these spots dwell soothing joys; therefore here is the understanding 

 or mind. All the rest of the soul disseminated through the whole body obeys and moves at the will and inclina- 

 tion of the mind." — De R. N., Ill, 136-44. 



* IVR., 20t-20^. 



