556 



NA TURE 



[October i, 1908 



Jiuti'ition itself is only a constant process of r»-yroductiun : 

 for the material of the organism is constantly changing. 

 Not only is there constant molecular change, but the living 

 cells are constantly being cast oft and reproduced. It is 

 only a step from this to the reproduction of lost parts which 

 occurs so readily among lower organisms ; and a not much 

 greater step to the development of a complete organism 

 from a single one of the constituent cells of an embryo in 

 its early stages. In all these facts we have simply mani- 

 festations of the fundamental characters of the living 

 organism. The reproduction of the parent organism from 

 a single one of its constituent cells separated from the body 

 seems to me only another such manifestation. Heredity, 

 or, as it is sometimes metaphorically expressed, organic 

 memory, is for Biology an axiom and not a problem. The 

 problem is why death occurs, what it really is, and why 

 only certain parts of the body are capable of reproducing 

 .the whole. These questions carry us, at least in part, 

 beyond the present boundary lines of Biology. They 

 involve those ultimate questions which, as has just been 

 pointed out, it is the province of Philosophy to deal with. 



To turn to another set of questions, the distinctively 

 biological standpoint in Biolog\' involves a change in what 

 has in recent times become the ordinary attitude towards 

 organic evolution. Since our conception of an organism is 

 different in kind, and not merely in degree, from our con- 

 ception of a material aggregate, it is clear that in tracing 

 back life to primitive forms we are getting no nearer to 

 •what is called abiogenesis. The result of investigation in 

 this direction can only be to extend further the domain 

 of Biology and widen biological ideas. Our aim must be, 

 in short, not to reduce organic to inorganic phenomena, 

 but to bring inorganic phenomena into the domain of 

 Biology. 



I am well aware that it will be strongly maintained 

 that the change of front which I have urged as necessary 

 involves the giving up of all real attempt at scientific 

 explanation in Biology. As already explained, this is a 

 philosophical question, and I shall not attempt to deal 

 further with it here. What immediately concerns us as 

 biologists is whether the change of front will further or 

 hinder biological advance, particularlv in Physiology. Now 

 the first requisite of a working hypothesis is that it should 

 work, and I have tried to point out that as a matter of 

 fact the phvsico-chemical theorv of life has not worked 

 in the past and can never work. .As soon as we pass 

 beyond the most superficial details of physiological activity 

 It becomes unsatisfactory ; and it breaks down completely 

 when applied to fundamental physiological problems, such 

 as that of reproduction. Those who aim at physico- 

 chemical explanations of life are simply running their heads 

 at a stone wall, and can only expect sore heads as a con- 

 sequence. It seems to me that the proposed change of 

 front is only the conscious adoption of a common-sense 

 idea which is somewhat vaguely, perhaps, present in the 

 minds of all men, and which has in reality guided biological 

 advance in the past. This idea, as I have tried to show, 

 is a working hypothesis which actually works, and affords 

 clear guidance for future advance. 



I would fain add a few words as to the relation of 

 Physiology to Psychology and Ethics : for this is a subject 

 of deep human interest. \A*e know that at any rate the 

 higher organisms are conscious and intelligent. This fact 

 brings Physiology into touch with a new element in the 

 behaviour of organisms. The subject is far too great a 

 one for me to attempt to discuss here, but I should like 

 to say that it appears to me very clear that just as Biology 

 is something more than Physics and Chemistry, so Psycho- 

 logy is something more than Physiology, with the added 

 assumption that consciousness is tacked on to certain 

 phvsiological processes, if such a crude conception has any 

 definite meaning. We can, it is true, by a process of 

 abstraction treat sensation from the purely physiological 

 side, as in investigating the physiology of the sense-organs; 

 but this is Physiologv and nothing else ; for we are leaving 

 out of account the distinctive elements of consciousness. 

 .'Vt our present stage of knowledge life is not intelligence, 

 and men or animals as intelligent individuals involve a 

 deeper aspect of reality than Biology deals with. Our 

 fundamental physiological working hypothesis cannot be 

 successfully applied to the phenomena of intelligence, and 



KG. 20:21, VOL. 78] 



the sooner and more definitely this is realised the better 

 for Physiology. 



In conclusion, let me endeavour to state shortly the main 

 contention which I have endeavoured to place before you. 

 It is that in Physiology, and Biology generally, we are 

 dealing with phenomena which, so far as our present 

 knowledge goes, not only differ in complexity, but differ 

 in kind from physical and chemical phenomena ; and that 

 the fundamental working hypothesis of Physiology must 

 differ correspondingly from those of Physics and Chemistry. 



That a meeting-point between Biology and Physical 

 Science mav at some time be found, there is no reason for 

 doubting. But we may confidently predict that if that 

 meeting-point is found, and one of the two sciences is 

 swallowed up, that one will not be Biology. 



SECTON K. 



BOTANY. 



Opening .\ddress by F. F. Blackman, M.A., D.Sc, F.R.S., 

 Pesident of the Section. 



The Manifestations of the Principles of Chemical Mechanics 

 ill the Living Plant. 



The Uniformity of N.4ture. 



.\mong the phenomena of nature Man finds himself to be 

 one of medium magnitude, for while his dimensions are 

 about a billion times as great as those of the smallest 

 atoms that compose him they are also about one-billionth 

 part of his distance from the centre of his solar system. 



From the vantage point of this medium magnitude the 

 man of science scans eagerly the whole range of natural 

 phenomena accessible to him with a strenuous desire for 

 unity and simplification. 



Bv the unwearying study of special sections of this long 

 front of natural phenomena special guiding principles have 

 been detected at work locally. No sooner has this been 

 accomplished than, in obedience to this desire for con- 

 tinuitv throughout, such principles have been freely ex- 

 tended on either side from the point of discovery. 



Thus, the theory of probability, which dealt at first with 

 so limited an occupation as drawing white and black balls 

 out of an opaque bag, now is known as the only determin- 

 able factor in such remote things as the distribution of 

 the duration of human lives and the effect of concentration 

 of the colliding molecules in a solution upon the rate of 

 their chemical change. Again, the principle of evolution 

 discovered among living things has been extended, until to 

 speak of the evolution of societies, of solar systems, or 

 of chemical elements is now but commonplace. 



The biologist, with all his special difficulties, has at 

 least the limitation that he is only concerned with the 

 middle range of the interminable hostile front of natural 

 phenomena, and that for him is ordained the stubborn 

 direct attack, leaving the brilliant attempts at outflanking 

 movements to the astronomers on the one wing and the 

 workers at corpuscular emanations on the other. 



The atoms and molecules that the biologist has to deal 

 with do not differ from those passing by the same names 

 in the laboratories of chemistry and physics (at least no 

 one suggests this), and their study may therefore be left 

 to others. At the other end of the scale, with astronomical 

 magnitudes we have not to deal, unless indeed we yield 

 to the popular clamour to take over the canals on Mars 

 as phenomena necessarily of biological causation. 



In the study of that particular range of phenomena which 

 is the special allotment of the physiologists, animal and 

 vegetable, we have had ever before us the problem of 

 whether there is not here some discontinuity in nature; 

 whether the play of molecular and atomic forces occur- 

 ring outside the living organism can ever account for the 

 whole of the complexity and correlation of chemical and 

 phvsical interactions demonstrable within the living struc- 

 ture. 



.As vet we are of course far from any answer to this 

 question, and no one in a scientific assembly like this 

 will call upon us for prophecies. Yet the subject to which 

 I shall devote my .Address has a bearing upon this ques- 

 tion. I propose to consider a particular aspect of the 

 relation of chemical changes in a test-tube to those taking 



