More on Berzelius and the vital force

To the Editor: In a lucid paper (1) Timothy 0. Lipman has once more carried through an analysis of the influence. Wohler's preparation of urea had on ...
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More on Berzelius and the Vital Force T o the Editor: In a lucid paper (1) Timothy 0.Lipman has once more carried through an analysis of the influence Wohler's preparation of urea had on the vitalistic concepts in nineteenth century organic chemistry. Although Lipman has brought no unknown evidence to light and although his conclusions are on a line with those of a number of earlier writers (3-4), the merit of the paper is unquestionable in so far as the significance of Wohler's synthesis is still heavily overestimated in most textbooks on organic chemistry and gives the student a totally false impression of historical reality. A particular point of merit is that Lipman has given the right sense to the German "Naturphiiosoph," which has been misinterpreted and mistranslated by a number of English writers on the subject. Our concern here is not, however, to enter into a discussion on points of interpretation, but to point out some facts concerning Berzelius' views on vitalism. It is generally stated that Berzelius was a convinced vitalist and held this view to the last (1, 6). We shall not here attempt to give a full survey of the

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views on vitalism held by Berzelius. This has been done elsewhere in the course of our studies on vitalism carried through a t the History of Science Department a t this University (6). Therefore we shall content ourselves with his views after 1827. The Vitalistic Teachings of Berzelius

In 1827 Berzelius published his textbook on organic chemistry simultaneously in Sweden and Germany. The hook is introduced with some general remarks on the special character of organic Nature and organic chemistry. It is here stated that: In living Nature the elements seem to obey entirely different The essence of the living body laws than they do in the dead consequently is not founded in its inorganic elements, but in some other thing, which disposes the inorganic element* . . to produce a certain result,~specificand characteristic of each apeciea . . . This "somethmg" which we call vital force is situated fully autside the inorganic elements and is not one of their original praperties as are gravity, impenetrability, electrical polarity, and so on (7).

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If one compares this teaching with those of the vitalists of the time, one can hardly deny that they represent a

genuine vitalistic point of view. This introduction is almost the only evidence we possess of vitalistic views propounded by Berzelius. I n the original, of which we have only taken a few characteristic sentences, the discussion is extended over several pages. The Fifth Edition of the Textbook

The introduction just cited is to be found in all three German editions of the textbook, which appeared as the first, third, and fifth (unfinished) editions in 1827,1837, and 1847 respectively. It is this fact whioh lies behind the assertion that Berzelius to his very last (he died in 1848) was a convinced vitalist. However, there is a small alteration in the fifth edition. I n the sentence: "This something, which we call vital force is situated fully outside. . the part of the sentence in italics is omitted and a few pages later we find a discussion of the meaning of the term "vital force," which was not included in the earlier editions. It is, says Berzelius, necessary to make the right understanding of this term clear to oneself. "It is evident that if one is to understand. . . by the effect of the vital force, something other than the characteristic conditions, cooperating in various ways, under which the usual natural forces are put into action in organic Nature and that, if it is thought of as a specific chemical power in living Nature, this inclination is a mistake (S)." At this point we must consider the two aspects of vitalism which we here distinguish by calling them the physiological and the chemicul vitalism. The physiological point of view merely denies that life can generate itself; hut once it is generated, by multiplication or by creation, it is subject to the general natural laws, although in a very complex manner. The chemical vitalism on the other hand asserts the existence of a chemical aflinity which acts only within the living body and whioh is directed against the usual (inorganic) affinities. It is against this last, chemical vitalism, that Berzelius is speaking in his denial of the vital force. Now it is evident that if the introduction is to have any meaning a t all, this meaning must not contradict the discussion of the term "vital force." Bearing this in mind, a second reading of the whole introduction indicates that it is not intended to represent a dogma of chemical vitalism, but is stating a belief in physiological vitalism which does not deny the applicability of the ordinary natural laws. This introduces the necessary consistency in the views expressed. This also explains why Berzelius in the fifth edition inserted between the original introduction and the discussion of vital force a digression on the self-generation of life.

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Other Remarks on the Vital Force by Berzelius

The opinion put forward in the 1847 edition of the textbook was not new a t that time. Very nearly the same argument is used in a paper from 1838 (9). I n a private letter to the botanist C.A. Agardh, critizing Agardh's new book on botany, Berzelius likewise denies the existence of a chemical vital force. As the letter which dates from 1831 has not been drawn to the attention of English scholars, as far as we know, the relevant passages will be given here in an English transtion: On pages 3

t o 5 the forces which

act within living bodies are

said not to be chemicalforces. Many peoplesay thesameas you; but how does one know it? You say: became one cannot attificially reproduce the products of organic Nature. Thia proves nothing. Any proof based in inability is no proof. To suppose that the elements are imbued with other fundamental forces in organic Nature than in the inorganic is an absurdity. The difference between the products ie due to the different conditions under which the forces work and these can vary inEnitely; but the fact that we cannot rightly understand the conditions prevailing in organic Nature gives us no sufficient reason to adopt other forces. Berzelius and Organic Synthesis

Berzelius is known as one of those early organic chemists who denied the possibility of organic synthesis. This is not, however, founded on the concept of vital force and, as we have seen in the letter to Agardh, he does not regard the impossibility of synthesis as evidence for the vital force. Indeed, when one follows the whole development of the concepts of Berzelius it becomes clear that the theoretical impossibility of synthesis was foundrd ou thc, t~lrrtrwhrmicnltheory in connrction with certain emoirical facts. which soace does not :~llow us to discuss. 'until the synthesis of acetic acid by Kolbe in 1844 the only total synthesis known was the Wohler synthesis; it is therefore interesting to note that Berzelius already in 1843 was inclined to believe in the artificial production of animal products (11). What may have been the grounds for this remarkable change from 1827 to 1843? The grounds are several. First, the general increase in knowledge of organic compounds, e.g., the great investigation of uric acid by Liebig and Wohler in 1837 with the remarkable result that one of the transformation products of uric acid turned out to be allantoin, known from the allantoisliquor. Second, the concept of catalysis (1835) had led to a n understanding of the chemical processes of the living organism. Prior to that time catalysis had vaguely been ascribed to nervous action lrnown to result from electricity. There is no doubt that Berzelius in the catalytic force saw the real clue to the chemistry of the living body in the frame of electrochemical theory ( I d ) . Third, the success electrochemical theory had in those years in explaining organic compounds is to be considered. Conclusion

We have tried in this note to bring forward some evidence against the general view of Berzelius as a convinced vitalist, and have tried to advocate the view that Berzelius actually was a physiological vitalist and so never denied the validity of the general natural laws in living matter. He did not represent a genuine chemical vitalism. His use of "vital force" is synonymous with the expression "the cooperating of the usual natural forces in organic Nature." This is in accord with his use of the term in the purely materialistic teachings of his "Animal Chemistry" published 1806 to 1808 (IS). It should be noted that a n important source of ours is the very same which elsewhere has been used to advocate a contrary view. Thus historical sources are not to be used as a reservoir of statements to support ones expectations. An extended knowledge of the whole content of the source is necessary in forming the picture of historical reality. As a last remark, we would like to emphasize that Volume 42, Number 7, July 1965

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there are two aspects of Berzelius' vitalism. Was it right of the contemporaries of Berzelius to conclude he was a vitalist? Of course it was, if the only source they had was the early editions of the textbook. Was Berzelius really a vitalist? This is of interest mainly for the historian of science-was it with historians in mind that he felt it necessary to explain his real viewpoint more sharply in the last edition of his textbook, his "chemical testament?" Literature Cited (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11)

LIPMAN, TIMOTRY O., THIS JOURNAL, 41,452 (1964). WALDEN, PAUL,Naluru%8senschaflm, 16, 835 (1928). MCKIE,DOUGLAS, Naluw, 153, 608 (1044). JACQUES,J., Rev. Hist. Sci. Appl., 3,32 (1950). P A R T I N ~ TJ.~ N R.,, "A History of Chemistry," Mscmibn and Co., Ltd., London, 1964, Vol. 4, p. 252. J#RGENSEN, B. S., Centaurus, in press. BER~ELIU~, J. J., "Lehrbnch der Chemie," 1st ed., Arnoldischen Buchhandlunp. -. Dresden and Leipzi~. . -. 1827. Vol. 3. pp. 135-8. BERZELIU~, J. J., "Lehrbuch der Chemie," 5th ed., Arnoldischen Buchhandlung, Dresden and Leipzig, 1847, Vol. 4, 00. 6. =.~ 5. ~, Kungliga Svenska Vetenskspsacsdemiens Hmdligar, 1838, pp. 77-111. J. J., Bvev (ed. Soderbaum), 4.71 (1831). BERZELIUS, J. J., "Lehrhuch der Chemie," 4th ed., ArnoldBERZELIUS, ischen Buehhandlung, Dresden and Leipzig, 1843, Vol. 1, &,. l l d

(12) BERZELIUS, J. J., Jahresberichl, 18, 563 (1838). J. J., "Djurkemi," 1-2, Stockhulm 1806-08. (13) BERZELIUS,

Bent Sglren Jglrgensen

T o the Editor: I thank Bent Sglren JGrgensen for his kind words about my paper. Jglrgensen has performed a useful piece of scholarship in remindimg us of the changes in the fifth edition of Berzelius' textbook and in translating his letter. The point which he raises-that Berzelius' views shifted with time--seems to he conclusively preeented. Nevertheless, while agreeing that there was a change, I cannot agree with Jglrgensen's interpretation of the nature of this change, nor do I think that his terms physiological and chemical vitalism are fruitful tools for analysis of Berzelius or his period. M y first objection to Jglrgensen's discussion is that physiological vitalism, as he defines it, does not explain Berzelius' introduction to the fifth edition of his textbook. Jglrgensen asserts that Berzelius' statement, "in living nature the elements seem to obey entirely different laws than they do in the dead," does not contradict the subsequent statement, "if. . . [the vital force] is thought of as a specific chemical power in living nature, this inclination is a mistake," because the first statement expresses Beraelius' belief in physiological rather than chemical vitalism. By Jglrgensen's definition physiological vitalism concerns itself only with generation. Once the organism is produced, he says, the operating forces of the organism are governed by the general inorganic laws. It seems to me, however, that 395 / lournal o f Chemical Education

Berzelius does not restrict "living nature" to the generation of life but includes within its scope the maintenance and existence of life as well, so that his introduction is not an example of physiological vitalism. Examination of JCgensen's section headed "Other remarks" shows a thud type of statement by Berzelius. In the letter to Agardh he does not deny a chemical vital force, but says rather that it is not known whether or not one exists because a valid proof is lacking. There is a significant diierence between saying, on the one hand, that there is no vital force, and, on the other, that there is no proof for the existence of a vital force. Hence, there are three types of statement which need explanation. Before attempting to clarify Berzelius' position, I would question the usefulness of the terms chemical and physiological vitalism for two reasons. The first is that these terms, if we are to accept them, are quite restrictive in their use. As Jglrgensen seems to define them, there is no allowance for the possibility that one could believe in the simultaneous operation of both a vital force and the natural forces. Yet this middle ground was the position held by Justus van Liehig.' The second reason for questioning Jglrgensen's terms is on more fundamental grounds. The purpose of a term like vitalism is to clarify the thought of an individual for our greater understanding. If a term does not advance us in our analysis, or worse still, if the term merely confuses the issue, then obviously the term should not be used. We can often designate certain aspects of the thought of an individual as vitalistic, hut to term such a person a vitalist would be to do him an injustice and accomplish no useful analytic function. For instance, we can find vitalistic thought in the French physiologist Claude Bernard,%"hut to designate him a vitalist hecomesabsurd. Thus, it makes good analytic sense to heed Everett Mendelsohn'sa observation that we ought to worry less about rigidly categorizing various nineteenth century scientists as this or that type of vitalist and pay more attention to the actual content of their work and thought. Rather than coining new terms or modifying old, it may be more profitable to examine the structure and content of the explanatory models a scientist uses in his theory construction. In this way we can examine the physical, chemical, and vitalistic aspects of the work and thought, and then leave it there. During the mid-decades of the nineteenth century there were a t least four approaches to the living organism. There were those who still followed the teachings of a man like Xavier Bichat, contending that it was impossible to study the organism in terms of

'GOODNELD,G. J., "The Growth of Scientific Physiology," Hutchinson and Co. Ltd., London, 1960; LIPMAN, TIM-Y O., "Justus von Liehie: a Studv of Exolanatorv Vitalism." unoub lished undergraduate honarsthesis, bamrnittke on the kietok of Science, Harvard University, 1964. ~ E R N A R CLAUDE, D, "An Introduction to Experimental Medicine," translated by HENRYCOPLEYGREENE,Dover l'ublic~r tions. Inc., New York, 1957, (a) p. 93; (b) pp. 6 6 7 . MENDELSOHN, EVEREIT,"Physical Models and Physiological Concepts: Explanation in Nineteenth Century Biology," in "Boston Studies in the Philosonhv of Science." Vol. 2. Humanities Press, New York, in press: I am indebted t k Professor Mendelsohn for his help in preparing this letter.