UNPROVED, NOT IMPOSSIBLE. n 



tion : " How did life originate on these unknown, extra-mundane 

 sources of creative messengers ? " There are only two possible 

 answers to these questions, viz., spontaneous generation, or a 

 miracle. 



As a matter of reason, we are therefore obliged to assume that, 

 at some definite moment in the past, organised living beings were 

 produced from unorganised potentially organic substances ; and 

 further, that such creative power may still be operating, may 

 perhaps be performing at present. The possibility cannot be 

 gainsaid. 



That bacteria are the result of this primary creation of living 

 beings is very questionable and even improbable, since their 

 structure is much more complicated than is consistent with their 

 presumed origin directly from chemical elements, unmodified by 

 changes in passing through simpler intermediate organisms. 



Many investigators, and amongst them C. NAGELI (I.), assumed 

 that these lowest forms really exist, although undiscovered at 

 present, and in his important and highly suggestive work on the 

 Theory of Descent which also contains a fine chapter on "the limits 

 of knowledge in natural science " this author touches upon the 

 question under consideration. He calls these presumptive con- 

 necting links Probien (pre-existing), on the ground of their being 

 the predecessors of all known forms of living beings. Such a 

 Probion resulting from spontaneous generation would be " merely 

 a drop of homogeneous structureless plasma, devoid of any definite 

 form and composed of albuminates, associated only with the com- 

 pounds necessary for nutrition." 



" We must assume " says de Bary " that organisms must at 

 one time have originated from organisable but unorganised sub- 

 stances, without progenitors. ... To prove such a primary creation 

 of a living being is of the highest interest, and exercises the same 

 fascination on the investigator as the expectation of the homunculus 

 in the phial did on the alchemist. The experience of centuries 

 has, however, shown that the homunculus when it actually appeared 

 was simply a small imp which had been secretly passed into the 

 flask by sleight of hand. . . . Therefore admitting all imaginable 

 possibilities the law, based on experience, of origin from ancestors, 

 corresponds with the enlightened state of our knowledge, and this 

 is the starting-point that must be taken in a work which has to 

 deal with the exact sciences." 



