4:36 Dr. St. George Mivart [June 5, 



statements, tlicn cither we must argue in a circle, or our process of 

 proof must go on for ever without coming to a conclusion, which 

 meaus there could be no such thing as "proof" at all. 



Therefore the grounds of certainty which any fundamental pro- 

 position may possess, cannot be anything external to it — which 

 would imjjly this impossible proof. The only ground of certainty 

 which an ultimate judgment can possess is its own self-evidence — 

 its own manifest certainty in aud by itself. All proof, all reasoning 

 must ultimately rest upon truths which carry with them their own 

 evidence and do not therefore need proof. 



It is possible that some of my hearers may be startled at the 

 suggestion of believing anything whatever on its own evidence, 

 fancying it is equivalent to a suggestion that they should believe 

 anything blindly. This, I think, is due to the following fact of 

 mental association. The immensely greater part of our knowledge 

 is gained by us indirectly — by inference or testimony of some kind. 

 We commonly ask for a proof, with regard to any new and 

 remarkable statement, and no truths are brought more forcibly home 

 to our minds than are those demonstrated by Euclid. Thus it is that 

 many persons have acquired a feeling that to believe anything which 

 cannot be proved, is to believe blindly. Hence arises the tendency 

 to distrust what is above and beyond proof. We are apt to forget what 

 on reflection is manifest, namely that if it is not blind credulity to 

 believe what is evident to us by means of something else, it must be 

 still less blind to believe that which is directly evident in and by 

 itself. 



And self-conscious reflective thought tells me clearly, that the 

 law of contradiction is not only implied by all science, and necessary 

 to the validity of all science, but that it is, as I said, an absolutely 

 necessary truth which carries with it its own evidence. It must be 

 a truth then applicable both to the deepest abyss of past time and 

 the most distant region of space. But here again I think it possible 

 that one or two of my hearers may be startled, and perhaps doubting 

 how things in this resj)ect may be in the Dog star now or how they 

 were before the origin of the solar system. I fancy I hear some one 

 asking, " How is it possible that we, mere insects, as it were, of a day, 

 inhabiting an obscure corner of the universe, can know that anything 

 is and must be true for all ages and every possible region of space ? " 



In the first place I think the difficulty which may be thus felt is 

 due to the abstract form of the law of contradiction. And yet, as 

 I said before, it is but the summing up of all the particular instances 

 as to each one of which no difficulty at all is felt, but each is clearly 

 seen to be true. Any man who really doubted whether if his legs 

 were cut off they might not at the same time remain on, would have 

 a mind in a diseased condition. There is, however, another reason 

 which indisposes some persons to see the necessary force of this law. 

 It is due, I think, to a second fact of mental association. 



Things which are very distant or which happened a long time 



