406 INDUCTION. 



CHAPTER XXII. 



OF UNIFORMITIES OF CO-EXISTENCE NOT DEPENDENT ON CAUSATION. 



§ 1. The order of the occurrence of phenomena in time, is either succes- 

 sive or simultaneous ; the uniformities, therefore, which obtain in their oc- 



perience, which I have not been able to accord to them. He does this on the faith of our 

 faculty of abstraction, in which he seems to recognize an independent source of evidence, not 

 indeed disclosing truths not contained in our experience, but affording an assurance which 

 experience can not give, of the universality of those which it does contain. By abstraction 

 M. Taine seems to think that we are able, not merely to analyze that part of nature which we 

 see, and exhibit apart the elements which pervade it, but to distinguish such of them as are 

 elements of the system of nature considered as a whole, not incidents belonging to our limited 

 terrestrial experience. I am not sure that I fully enter into M. Taine's meaning ; but I con- 

 fess I do not see how any mere abstract conception, elicited by our minds from our experi- 

 ence, can be evidence of an objective fact in universal Nature, beyond what the experience it- 

 self bears witness of; or how, in the process of interpreting in general language the testimony 

 of experience, the limitations of the testimony itself can be cast off. 



Dr. Ward, in an able article in the Dublin Review for October, 1871, contends that the uni- 

 formity of nature can not be proved from experience, but from "transcendental considera- 

 tions " only, and that, consequently, all physical science would be deprived of its basis, if such 

 transcendental proof were impossible. 



When physical science is said to depend on the assumption that the course of nature is in- 

 variable, all that is meant is that the conclusions of physical science are not known as absolute 

 truths : tlie truth of them is conditional on the uniformity of the course of nature ; and all 

 that the most conclusive observations and experiments can prove, is that the result arrived at 

 will be true if, and as long as, the present laws of nature are valid. But this is all the as- 

 surance we require for the guidance of our conduct. Dr. Ward himself does not think that 

 his transcendental proofs make it practically greater; for he believes, as a Catholic, that the 

 course of nature not only has been, but frequently and even daily is, suspended by supernatu- 

 ral inteiTention. 



But though this conditional conclusiveness of the evidence of experience, which is sufficient 

 for the purposes of life, is all that I was necessarily concerned to prove, I have given reasons 

 for thinking that the uniformity, as itself a part of experience, is sufficiently proved to justify 

 undoubting reliance on it. This Dr. Ward contests, for the following reasons : 



First (p. 315), supposing it true that there has hitherto been no well authenticated case of 

 a breach in the uniformity of nature; "the number of natural agents constantly at work is 

 incalculably large ; and the observed cases of uniformity in their action must be immeasur- 

 ably fewer than one thousandth of the whole. Scientific men, we assume for the moment, 

 have discovered that in a certain proportion of instances — immeasurably fewer than one 

 thousandth of the whole — a certain fiict has prevailed ; the fact of uniformity ; and they have 

 not found a single instance in which that fact does not prevail. Are they justified, we ask, 

 in inferring from these premises that the f^ict is universal ? Surely the question answers it- 

 self. Let us make a very grotesque supposition, in which, however, the conclusion would 

 really be tried according to the arguments adduced. In some desert of Africa there is an 

 enormous connected edifice, surrounding some vast space, in which dwell certain reasonable 

 beings, who are unable to leave the inclosure. In this edifice are more than a thousand 

 chambers, which some years ago were entirely locked up, and the keys no one knew where. 

 By constant diligence twenty-five keys have been found, out of the whole number ; and the 

 corresponding chambers, situated promiscuously throughout the edifice, have been opened. 

 Each chamber, when examined, is found to be in the precise shape of a dodecahedron. Are 

 the inhabitants justified on that account in holding with certitude that the remaining 975 

 chambers are built on the same plan ?" 



Not with perfect certitude, but (if the chambers to which the keys have been found are 

 really " situated promiscuously ") with so high a degree of probability that they would be justi- 

 fied in acting upon the presumption until an exception appeared. 



Dr. Ward's argument, however, does not touch mine as it stands in the text. My argu- 

 ment is grounded on the fact that the uniformity of the course of nature as a whole, is coa- 



