4 THE LANGUAGE OF BOTANISTS. 



naturalists of the day, or of the hypotheses which happened to be then in vogue. 

 The progress of true knowledge is too often hindered by the fact that men exalt 

 their speculative theories to the position of " laws of nature ", and when they first 

 encounter contradictory evidence twist and turn it until it appears actually to 

 verify those theories. We need not inquire in these instances how much is due 

 to self-deception and how much to prejudice and dogmatism on the part of the 

 investigators. Certain it is that such a perverse method of research, especially 

 when supported by the authorized beliefs of the thoughtless multitude, acts as a 

 drag on true science. Fortunately, however, it is nothing worse than a drag. 

 For, sooner or later, the conviction again asserts itself that our notions respecting 

 the history of plants must be derived from the facts observed in their entirety and 

 purity, instead of facts being made to fit a preconceived opinion some being 

 explained away as exceptions, whilst others are altogether ignored and sup- 

 pressed. 



In all sciences for which it is requisite to invent technical terms and in Botany 

 no less than in others we find that the terminology bears traces of ideas formed 

 at earlier periods, and now rejected as being based on insufficient experiment or 

 imperfect observation, on self-deception or prejudice, as the case may be. The 

 question has, therefore, repeatedly been raised whether it is better to retain such 

 names and modes of expression, although they are likely to suggest wrong ideas to 

 students, or to abolish them and substitute new ones in their stead. There are 

 strong arguments for both courses. The chief advantage of retaining the old 

 terms is that readers of modern works are thereby enabled to understand more 

 easily the writings of older botanists. We have also to consider the probability 

 that in rejecting old terms and inventing new ones we may fall into the same 

 errors as our predecessors. Any one who has worked in the field of Botany for 

 more than forty years, as I have done, must have found that on an average every 

 ten years prevailing ideas have undergone a change. He has seen how theories, 

 which for a time influenced every branch of the science, and were actually standard 

 conceptions in many departments of research, have sooner or later had to give 

 place to new ones. He knows how often a naturalist is compelled, in consequence 

 of fresh and unexpected discoveries, to let go a position which he has considered 

 impregnable, and which has become endeared to him by long familiarity. Thus, 

 experience teaches diffidence, and one learns to attribute only a temporary value, 

 so to speak, even to one's own original theories, and to rest assured that, in a 

 few decades, what now appears to be nearest the truth will be superseded by 

 something else which comes still nearer to it. 



But if, whenever a fresh stage of knowledge were reached, all terms and 

 phrases which had become antiquated and no longer quite applicable were 

 abandoned and replaced by others, and if in addition new names were introduced 

 corresponding to every modification in the results obtained by observing all the 

 different processes and appearances with which we have to deal, our science would 

 inevitably be rendered far less accessible and this consequence would be much to 



