308 EVOLUTION [CHAP. IV 



Letter 223 In regard to thorns and spines I suppose that stunted 

 and [illegible] hardened processes were primarily left by the 

 abortion of various appendages, but I must believe that their 

 extreme sharpness and hardness is the result of fluctuating 

 variability and "the survival of the fittest." The precise 

 form, curvature and colour of the thorns I freely admit to be 

 the result of the laws of growth of each particular plant, or 

 of their conditions, internal and external. It would be an 

 astounding fact if any varying plant suddenly produced, with- 

 out the aid of reversion or selection, perfect thorns. That 

 Natural Selection would tend to produce the most formidable 

 thorns will be admitted by every one who has observed the 

 distribution in South America and Africa (vide Livingstone) 

 of thorn-bearing plants, for they always appear where the 

 bushes grow isolated and are exposed to the attacks of 

 mammals. Even in England it has been noticed that all 

 spine-bearing and sting-bearing plants are palatable to 

 quadrupeds, when the thorns are crushed. With respect to 

 the Malayan climbing Palm, what I meant to express is that 

 the admirable hooks were perhaps not first developed for 

 climbing ; but having been developed for protection were 

 subsequently used, and perhaps further modified for climbing. 



Letter 224 To'J. D. Hooker. 



Down, Sept. 8th [1868]. 



About the Pall Mall. 1 I do not agree that the article was 

 at all right ; it struck me as monstrous (and answered on the 



1 Pall Mall Gazette, August 22nd, 1868. In an article headed "Dr. 

 Hooker on Religion and Science," and referring to the British Associa- 

 tion address, the writer objects to any supposed opposition between 

 religion and science. " Religion," he says, " is your opinion upon one 

 set of subjects, science your opinion upon another set of subjects." But 

 he forgets that on one side we have opinions assumed to be revealed 

 truths ; and this is a condition which either results in the further opinion 

 that those who bring forward irreconcilable facts are more or less wicked, 

 or in a change of front on the religious side, by which theological opinion 

 "shifts its ground to meet the requirements of every new fact that science 

 establishes, and every old error that science exposes " (Dr. Hooker as 

 quoted by the Pall Mall}. If theologians had been in the habit of recog- 

 nising that, in the words of the Pall Mall writer, " Science is a general 

 name for human knowledge in its most definite and general shape, what- 

 ever may be the object of that knowledge," probably Sir Joseph Hooker's 

 remarks would never have been made, 



