X ON THE STUDY OF BIOLOGY 279 



the light given out by the crackling of thorns 

 under a pot of which Solomon speaks. So far as 

 I recollect, Solomon makes use of the image for 

 purposes of comparison; but I will not proceed 

 further into that matter. 



Two things must be obvious: in the first place, 

 that every man who has the interests of truth at 

 heart must earnestly desire that every well- 

 founded and just criticism that can be made should 

 be made; but that, in the second place, it is essen- 

 tial to anybody's being able to benefit by criticism, 

 that the critic should know what he is talking 

 about, and be in a position to form a mental 

 image of the facts symbolised by the words he uses. 

 If not, it is as obvious in the case of a biological 

 argument, as it is in that of a historical or philo- 

 logical discussion, that such criticism is a mere 

 waste of time on the part of its author, and wholly 

 undeserving of attention on the part of those 

 who are criticised. Take it then as an illustration 

 of the importance of biological study, that there- 

 by alone are men able to form something like 

 a rational conception of what constitutes valuable 

 criticism of the teachings of biologists.* 



* Some critics do not even take the trouble to read. I 

 have recently been adjured with much solemnity, to state 

 publicly why I have " chan,e:ed my opinion " as to the value 

 of the palajontological evidence of the occurrence of evo- 

 lution. 



To this my reply is, Why should I, when that statement 

 was made seven years a.2:o'? An address delivered from tiie 

 Presidential Chair of the Geological Society, in 1870, may 



78 



