330 RAYMOND J. NOGAR 



cussion when they act as if the origin of the human body from pre- 

 existing and living matter were already completely certain and 

 proved by facts which have been discovered up to now and reason- 

 ing on those facts {per indicia hucusque reperta ac per ratiocinia 

 ex iisdem judiciis deducta, jam certa omnino sit ac demonstrata) 



10 



• • • 



On the face of things, there seems to be a fundamental dis- 

 agreement between the statements concerning the " fact of evo- 

 lution " made by most scientists today and those written in 

 Humani Generis. But this apparent disagreement is one found 

 not only in the dialogue between the theologian and the 

 scientist, or the philosopher and the scientist. There is fun- 

 damental ambiguity and apparent disagreement about the 

 significance and the validity of the proposition even among 

 scientists, as Olson's paper reveals. There cannot be true dis- 

 agreement in a dialogue, however, until there is fundamental 

 agreement about the meaning of the terms used in the discus- 

 sion. Minimal topical agreement must be had: men must agree 

 to disagree. 



The proposition " evolution is no longer a theory, it is a 

 fact " is valid or invalid depending upon the significance as- 

 signed to tw^o terms: " evolution " and " fact." If we disengage 

 the series of events called evolution from any discussion about 

 the ivay evolution might have taken place, we might begin with 

 the definition of evolution set down by Panel Two at the 

 Centennial Convention as our constant in the present dis- 

 cussion: 



Evolution is definable in general terms as a one-way, irreversible 

 process in time, which during its course generates novelty, diversity, 

 and higher levels of organization. It operates in all sectors of the 

 phenomenal universe but has been most fully described and ana- 

 lyzed in the biological sector.^^ 



This definition was agreed upon by Huxley, Emerson, Axelrod, 

 Dobzhansky, Ford, Mayr, Nicholson, Olson, Prosser, Stebbins, 

 Wright, and, presumably, by all other members of the Con- 



'"Ibid., p. 19. ''EAD, III, 107. 



