SESSION V. DISCUSSION 485 



work of Klieneberger-Nobel, who has demonstrated the regeneration of the so-called 

 L-form after filtration. 



Thus the new cellular theory, which denies the immutability of the principle that 

 'cells only arise from cells', is completely confirmed by the evidence of contemporary 

 microbiology. 



As concerns the world of microbes, the controversy between the old and new cellular 

 theories may be considered to have been concluded in favour of the latter. The position 

 is diff"erent as regards the field of investigation of the abiUty of the cells of higher plants 

 and animals to develop. In this field controversy is still going on. 



According to our evidence, division is not the only mechanism of production of cells 

 of higher Uving things. On the other hand, this evidence of ours has been criticized in a 

 number of papers. 



I maintain that our respected opponents, while sometimes correctly criticizing details 

 in our earher work, have not by any means confuted the fundamental data and the funda- 

 mental propositions of our theory in its appUcation to the cells of higher hving things. 

 During the last few years alone the proponents of the new cellular theory have published 

 more than 150 experimental studies confirming our evidence. The new cellular theory 

 has given a new direction to biology which cannot be ignored. 



In our conference the question of the origin of Ufe has been considered, essentially on 

 a biochemical level. In this cormection I want to direct your attention to the biochemical 

 investigation of living material carried out in the laboratory which I direct. These inves- 

 tigations confirm that metabolic processes can take place in material at a lower level of 

 organization than the cell. This applies not only to mitochondria, but also to other 

 protoplasmic formations. It also seems to us that biochemists should be interested in 

 the work of Diskina, in which it has been shown that compounds of nucleic acid with 

 crystalline trypsin form artificial nucleoproteins having many of the properties of natural 

 nucleoproteins. This agrees with the concept of the part played by nucleic acids in the 

 development of Uving material which we put forward long ago. 



In conclusion, I want to emphasize that the principle of the new formation of cells 

 from preceUular forms of Uving material opens up wide perspectives for the study of the 

 question of the origin of Ufe. The theory of the development of living material enables us 

 to make use of material closer to the original form of Ufe than the cell. This material 

 provides all transitional forms between the simplest preceUular material and the proto- 

 plasm of the ceU with all its morphological, chemical and biological complexity. I must 

 say a few more words. Our conference is not yet finished but it is already clear that many 

 people beUeve that the processes of life are not confined within the framework of ceUular 

 organization. This valuable exchange of ideas leads us closer to the conclusion that the 

 material of Ufe is protein which can develop and determine development. And then we 

 remember again with thankfulness the words of Frederick Engels: 'Life is the mode of 

 existence of albuminous bodies'. 



M. V. Vol'kenshtein (U.S.S.R.): 



The thermodynamics of irreversible reactions, to which Prof. Prigogine's very inter- 

 esting paper was devoted, is undoubtedly of great importance for an understanding of 

 the essential features of biological processes. In physics it seems perfectly natural and 

 inevitable to begin the study of new phenomena with a phenomenological, thermo- 

 dynamical analysis. Such an analysis always gives extremely incomplete, but nevertheless 

 particularly reliable information. The conclusions reached by the application of 'irrever- 

 sible thermodynamics' to biology are completely valid, although, naturally, they do not 

 reach the essence of the subject. 



Until recently 'irreversible thermodynamics' has been confined to a consideration of 

 linear relationships, based on the correlations of Onsager. Linear relationships are only 

 vaUd for processes which are taking place near to a state of equiUbrium. Biological pro- 

 cesses are clearly very far from a state of equiUbrium. This caused Eyring to deny the 

 appUcabiUty of irreversible thermodynamics to biology. Eyring prefers the alternative, 

 kinetic approach. 



