Appendix. 171 



and in entering this Scotch verdict of not proven, I simply accept 

 what I believe to be the correct interpretation of the best attain- 

 able evidence in the present state of our science. If new evi- 

 dence can be adduced which is subversive of this conclusion, we 

 must accept it without regard to our predilections or beliefs. To 

 reject the theory on such considerations is contrary to the scien- 

 tific method, and it is by this method alone that experimental 

 evidence should be interpreted. 



generation. To doubt longer is not to comprehend the question." Revue des 

 deux Mondes, Vol. LIV, 1864, p. 441. 



PASTEUR; "This conclusion which I have already formulated is unassail- 

 able. In the present state of science the hypothesis of spontaneous generation is a 

 chimera." Translated from a letter to Prof. Tyndall, dated Paris, February 8, 

 1876. The Lancet, Feb. 19, 1876, p. 296. 



HUXLEY ; " If in the present state of science, the alternative is offered us. 

 either germs can stand a greater heat than has been supposed, or the mole- 

 cules of dead matter, for no valid or intelligible reason that is assigned, are 

 able to rearrange themselves into living bodies, exactly such as can be de- 

 monstrated to be frequently produced in another way, I cannot understand 

 how choice can be, even fora moment doubtful. But though I cannot express 

 this conviction of mine too strongly, I must carefully guard myself against 

 the supposition that I intend to suggest that no such thing as Abiogenesis 

 ever has taken place in the past or ever will take place in the future. * * * 

 All I feel justified in affirming is that I see no reason for believing that the 

 feat has been performed yet.'.' President's Address, British Association, 1870. 

 Nature, Sept. 15, 1870, p. 403. 



BASTIAN : " On account of this a priori probability and in the face of this 

 evidence, I am, therefore, content, and, as I think, justified in believing that 

 Living things may and do arise de noro." Dr. B's. views have been often sum- 

 marized in his prolific writings, but I know of no more concise expression 

 of them than the above, from a closing paragraph of a series of papers "on the 

 Heterogeneous Evolution of Living Things." Mature, July 14, 1870, p. 228. 



LIONEL, S. BEALE : "I confess to being an opponent of the doctrine, but 

 simply because I cannot admit that the evidence yet adduced is at all con- 

 vincing. * * * The fact of a priori arguments having been so very much 

 dwelt upon, makes me think that the mind of the experimenter may have 

 been to some extent prejudiced (prepossessed) in favor of the doctrine he seeks 

 to support by new facts, and in this way they are calculated to excite in my 

 mind, however much I may resist, a doubt whether the inferences which 

 have been arrived at really have been deduced from facts of observation and 

 experiment o7.r." Nature, July 28, 1870, p. 2oi. 



SMITH, WOBTHINGTON G,: " It seems to me rational enough to suppose 

 that unicellular bodies and objects of the lowest possible organization may 

 be heterogeneously produced from the inorganic world." Nature, August 4, 

 1870, p. 276. 



VALENTIN: Prof. Physiology, Univ. Bern. -'On the whole, the hypothesis 

 of a spontaneous generation of plants or animals can only be regarded as a 



