184 REASONING. 



This I take to be the real and sufficient explanation of the paradoxical 

 truth, on which so much stress is laid by Dr. Whewell, that a scientifically- 

 cultivated mind is actually, in virtue of that cultivation, unable to conceive 

 suppositious which a common man conceives without the smallest difficul- 

 ty. For there is nothing inconceivable in the suppositions themselves ; the 

 impossibility is in combining them with facts inconsistent with them, as 

 part of the same mental picture ; an obstacle of course only felt by those 

 who know the facts, and are able to perceive the inconsistency. As far as 

 the suppositious themselves are concerned, in the case of many of Dr. Whe- 

 well's necessary truths the negative of the axiom is, and probably will be 

 as long as the human race lasts, as easily conceivable as the affirmative. 

 There is no axiom (for example) to which Dr. Whewell ascribes a more 

 thorough character of necessity and self-evidence, than that of the inde- 

 structibility of matter. That this is a true law of nature I fully admit ; 

 but I imagine there is no human being to whom the opposite supposition 

 is inconceivable — who has any difficulty in imagining a portion of matter 

 annihilated : inasmuch as its apparent annihilation, in no respect distin- 

 guishable from real by our unassisted senses, takes place evei'y time that 

 water dries up, or fuel is consumed. Again, the law that bodies combine 

 chemically in definite proportions is undeniably true; but few besides Dr. 

 Whewell have reached the point which he seems personally to have arrived 

 at (though he only dares prophesy similar success to the multitude after 

 the lapse of generations), that of being unable to conceive a world in which 

 the elements are ready to combine with one another " indifferently in any 

 quantity ;" nor is it likely that we shall ever rise to this sublime height of 

 inability, so long as all the mechanical mixtures in our planet, whether sol- 

 id, liquid, or aeriform, exhibit to our daily observation the very phenomenon 

 declared to be inconceivable. 



According to Dr. Whewell, these and similar laws of nature can not be 

 drawn from experience, inasmuch as they are, on the contrary, assumed in 

 the interpretation of experience. Our inability to "add to or diminish the 

 quantity of matter in the world," is a truth which " neither is nor can be 

 derived from experience ; for the experiments which we make to verify it 

 presuppose its truth When men began to use the balance in chem- 

 ical analysis, they did not prove by trial, but took for granted, as self-evi- 

 dent, that the weight of the whole must be found in the aggregate weight 

 of the elements."* True, it is assumed; but, I apprehend, no otherwise 

 than as all experimental inquiry assumes provisionally some theory or hy- 

 pothesis, which is to be finally held true or not, according as the experi- 

 ments decide. The hypothesis chosen for this purpose will naturally be 

 one which groups together some considerable number of facts alrea,dy 

 known. The proposition that the material of the world, as estimated by 

 weight, is neither increased nor diminished by any of the processes of na- 

 ture or art, had many appearances in its favor to begin with. It expressed 

 truly a great number of familiar facts. There were other facts which it 

 had the appearance of conflicting with, and which made its truth, as a 

 universal law of nature, at first doubtful. Because it was doubtful, exper- 

 iments \vere devised to verify it. Men assumed its truth hypothetically, 

 and proceeded to try whether, on more careful examination, the phenomena 

 which apparently pointed to a different conclusion, would not be found to 

 be consistent with it. This turned out to be the case ; and from that time 



* Phil, of Disc., pp. 472, 473. 



