to the english translation of the history of botany of julius von sachs.
i am gratefully sensible of the honourable distinction implied in the determination of the delegates of the clarendon press to have my history of botany translated into the world-wide language of the british empire. fourteen years have elapsed since the first appearance of the work in germany, from fifteen to eighteen years since it was composed,—a period of time usually long enough in our age of rapid progress for a scientific work to become obsolete. but if the preparation of an english translation shows that competent judges do not regard the book as obsolete, i should be inclined to refer this to two causes. first of all, no other work of a similar kind has appeared, as far as i know, since 1875, so that mine may still be considered to be, in spite of its age, the latest history of botany; secondly, it has been my endeavour to ascertain the historical facts by careful and critical study of the older botanical literature in the original works, at the cost indeed of some years of working-power and of considerable detriment to my health, and facts never lose their value,—a truth which england especially has always recognised.
but the present work is not a simple enumeration of the
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names of botanists and of their writings, no mere list of the dates of botanical discoveries and theories; such was not at all my plan when i designed it. on the contrary i purposed to present to the reader a picture of the way in which the first beginnings of scientific study of the vegetable world in the sixteenth century made their appearance in alliance with the culture prevailing at the time, and how gradually by the intellectual efforts of gifted men, who at first did not even bear the name of botanists, an ever deepening insight was obtained into the relationship of all plants one to another, into their outer form and inner organisation, and into the vital phenomena or physiological processes dependent on these conditions.
for the attainment of this end it was above all things necessary for me to form a clear judgment respecting the influence of the views and principles enunciated by the different authors on the further development of botanical science. this is to the historian of science the central point round which all beside should be disposed, and without which the entire work breaks up into a collection of unmeaning details, and it is one which demands knowledge of the subject, and capacity and impartiality of judgment. on questions connected with times long gone by the decision of the experts has in most cases been already given, though i myself found to my surprise that older authors had for centuries been regarded as the founders of views which they had distinctly repudiated as absurd, showing how necessary it is that the works of our predecessors should from time to time be carefully read and compared together. but in the majority of cases there is no dispute at the present day respecting the historical value, that is the operative
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influence on posterity, of works written three hundred or even one hundred years ago.
but it is a very different matter when the author of a book like mine ventures, as i have done for sufficient reasons but at the same time with regret, to sit in judgment on the works of men of research and experts, who belong to our own time and who exert a lively influence on their generation. in this case the author can no longer appeal to the consentient opinion of his contemporaries; he finds them divided into parties, and involuntarily belongs to a party himself. but it is a still more weighty consideration that he may subsequently change his own point of view, and may arrive at a more profound insight into the value of the works which he has criticised; continued study and maturer years may teach him that he overestimated some things fifteen or twenty years ago and perhaps undervalued others, and facts, once assumed to be well established, may now be acknowledged to be incorrect.
thus it has happened in my own case also in some but not in many instances, in which i have had to express an opinion respecting the character of works which appeared after 1860, and which to some extent influenced my judgment on the years immediately preceding them. but this was from fifteen to eighteen years ago when i was working at my history. it might perhaps be expected that i should remove all such expressions of opinion from the work before it is translated. in some few cases, in which this could be effected by simply drawing the pen through a few lines, i have so done; but it appeared to me that to alter with anxious care every sentence which i should put into a different form at the present day would serve no good
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purpose, for i came to the conclusion that my book itself may be regarded as a historical fact, and that the kindly and indulgent reader may even be glad to know what one, who has lived wholly in the science and taken an interest in everything in it old and new, thought from fifteen to eighteen years ago of the then reigning theories, representing as he did the view of the majority of his fellow-botanists.
however, these remarks relate only to two famous writers on the subjects with which this history is concerned. if the work had been brought to a close with the year 1850 instead of 1860, i should hardly have found it necessary to give them so prominent a position in it. their names are charles darwin and karl nägeli. i would desire that whoever reads what i have written on charles darwin in the present work should consider that it contains a large infusion of youthful enthusiasm still remaining from the year 1859, when the ‘origin of species’ delivered us from the unlucky dogma of constancy. darwin’s later writings have not inspired me with the like feeling. so it has been with regard to nägeli. he, like hugo von mohl, was one of the first among german botanists who introduced into the study that strict method of thought which had long prevailed in physics, chemistry, and astronomy; but the researches of the last ten or twelve years have unfortunately shown that nägeli’s method has been applied to facts which, as facts, were inaccurately observed. darwin collected innumerable facts from the literature in support of an idea, nägeli applied his strict logic to observations which were in part untrustworthy. the services which each of these men rendered to the science are still
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acknowledged; but my estimate of their importance for its advance would differ materially at the present moment from that contained in my history of botany. at the same time i rejoice in being able to say that i may sometimes have overrated the merits of distinguished men, but have never knowingly underestimated them.
dr. j. von sachs,
foreign fellow of the royal society.
würzburg, march 24, 1889.
