ON THE THEORY OF SCIENCE 349 



The energetical conception admits of that definiteness of represen- 

 tation which the condition of science demands and renders possible. 

 For each special manifold character of the field a special kind of 

 energy presents itself: science has long distinguished mechanical, 

 electric, thermal, chemical, etc., energies. All of these different 

 kinds hold together by the law of transformation with the mainten- 

 ance of the quantitative amount, and in so far are united. On the 

 other hand, it has been possible to fix upon the corresponding ener- 

 getical expression for every empirically discovered manifold. As a 

 future system of united energetics, we have then a table of possible 

 manifolds of which energy is capable. In this we must keep in mind 

 the fact that, in accordance with the law of the conservation, energy 

 is a necessarily positive quantity which also is furnished with the 

 property of unlimited possibility of addition; therefore, every par- 

 ticular kind of energy must have this character. 



The very small manifold which seems to lack this condition is 

 much widened by the fact that every kind of energy can be separ- 

 ated into two factors, which are only subject to the limitation that 

 their product, the energy, fulfills the conditions mentioned while 

 they themselves are much freer. For example, one factor of a kind of 

 energy can become negative as well as positive; it is only necessary 

 that at the same time the other factor should become negative, 

 viz., positive. 



Thus it seems possible to make a table of all possible forms of 

 energy, by attributing all thinkable manifold characteristics to the 

 factors of the energy and then combining them by pairs and cutting 

 out those products which do not fulfill the above-mentioned con- 

 ditions. For a number of years I have tried from time to time to 

 carry out this programme, but I have not yet got far enough to 

 justify publication of the results obtained. 



If we turn to the biological sciences, in them the phenomenon of life 

 appears to us as new. If we stick to the observed facts, keeping our- 

 selves free from all hypotheses, we observe as the general characteris- 

 tics of the phenomena of life the continuous stream of energy which 

 courses through a relatively constant structure. Change of substance 

 is only a part, although a very important part, of this stream. Espe- 

 cially in plants we can observe at first hand the great importance of 

 energy in its most incorporeal form, the sun's rays. Along with this, 

 self-preservation and development and reproduction, the begetting 

 of offspring of like nature, are characteristic. All of these properties 

 must be present in order that an organism may come into existence ; 

 they must also be present if the reflecting man is to be able by 

 repeated experience to form a concept of any definite organism, 

 whether of a lion or of a mushroom. Other organisms are met with 

 which do not fulfill these conditions; on account of their rarity, how- 



