DEMONSTRATION, AND NECESSARY TRUTHS. 271 



first by all persons in a sound state of their faculties. " We 

 now despise those who, in the Copernican controversy, could 

 not conceive the apparent motion of the sun on the heliocentric 

 hypothesis ; or those who, in opposition to Galileo, thought 

 that a uniform force might be that which generated a velocity 

 proportional to the space; or those who held there was some- 

 thing absurd in Newton's doctrine of the different refrangi- 

 bility of differently coloured rays ; or those who imagined that 

 when elements combine, their sensible qualities must be mani- 

 fest in the compound ; or those who were reluctant to give up 

 the distinction of vegetables into herbs, shrubs, and trees. 

 We cannot help thinking that men must have been singularly 

 dull of comprehension, to find a difficulty in admitting what 

 is to us so plain and simple. We have a latent persuasion 

 that we in their place should have been wiser and more clear- 

 sighted ; that we should have taken the right side, and given 

 our assent at once to the truth. Yet in reality such a per- 

 suasion is a mere delusion. The persons who, in such instances 

 as the above, were on the losing side, were very far, in most 

 cases, from being persons more prejudiced, or stupid, or narrow- 

 minded, than the greater part of mankind now are ; and the 

 cause for which they fought was far from being a manifestly 

 bad one, till it had been so decided by the result of the war. 

 ... So complete has been the victory of truth in most of 

 these instances, that at present we can hardly imagine the 

 struggle to have been necessary. The very essence of these 

 triumphs is, that they lead us to regard the views we reject as 

 not only false but inconceivable."* 



This last proposition is precisely what I contend for ; and 

 I ask no more, in order to overthrow the whole theory of its 

 author on the nature of the evidence of axioms. For what is 

 that theory ? That the truth of axioms cannot have been 

 learnt from experience, because their falsity is inconceivable. 

 But Dr. Whewell himself says, that we are continually led, 

 by the natural progress of thought, to regard as inconceivable 

 what our forefathers not only conceived but believed, nay even 



* Novum Organum Kenovatum, pp. 32, 33. 



