CHAMBERS'S INFORMATION FOR THE PEOPLE. 



This operation is technically termed the reduction 

 of syllogisms ; and the means employed is termed 

 the conversion of one or other, or both, of the 

 premises. 



We do not here enter into the processes of 

 reduction : they are more interesting exercises of 

 ingenuity, than operations of practical value. One 

 gains nothing by the application of the machinery 

 of abstract symbols to difficult deductions regard- 

 ing actual affairs : they are more a source of 

 bewilderment than a help. For practical pur- 

 poses, the best method is what we have recom- 

 mended namely, to throw the grounds of a 

 disputed conclusion into two propositions, and 

 see whether you have got a general proposition 

 concerning a class, and a proposition establishing 

 the identity of the subject of your conclusion with 

 that class. If your conclusion is supported by 

 two such propositions, common reason will instruct 

 you to proceed to it without hesitation. 



INDUCTION. 



Induction is the term applied to the process of 

 forming and establishing general propositions, 

 principles, laws, truths, or affirmations that is, 

 propositions which are applicable not to one case 

 only, but to all cases that have a certain definable 

 peculiarity ; as when we say, ' gold is heavy,' in 

 which case we affirm that all substances having 

 a certain colour and lustre are also of great 

 weight, or specific gravity. 



The first question that occurs respecting these 

 general affirmations is how and when are we 

 entitled to make such very broad assertions ? 

 We have no means of ascertaining the laws and 

 coincidences established in nature, except the 

 observation of what the world presents to us. If 

 we see that the qualities of yellowness and a 

 peculiar lustre are combined with heaviness, we 

 are entitled to assert the fact in as many in- 

 stances as we have verified by examination. In 

 like manner, if we see that water quenches fire, 

 we may assert that it is so in the cases noticed. 

 But there remains the grand difficulty namely, 

 why are we entitled to say that these coincidences 

 and successions take place not only in the cases 

 where they have been observed, but also in the 

 cases where they have not been observed, and in 

 all cases whatever ? For this is implied in every 

 general proposition. 



This question is answered by the observed fact, 

 that nature is uniform. There is a certain class 

 of coincidences or co-existences which are ever- 

 lasting and unvaried, and need only one observa- 

 tion to tell how they will be in every variety of 

 times and places ; and there is a certain class 

 of successions called Successions of Cause and 

 Effect, that are of the like unchanging kind, being 

 the same yesterday, to-day, and for ever. Hence, 

 in these cases, one observation is as good as a 

 million ; we are entitled to express or affirm 

 infinitely more than we actually find. It is from 

 nature's repeating herself in endless ways that 

 human labour is shortened to such an extra- 

 ordinary degree, that a few years of the short life 

 of man suffices for obtaining a very extensive 

 master}' of the vast and varied appearances of the 

 world. 



We have asserted that nature is uniform in her 

 coincidences of the properties of kinds, and in her 



358 



successions of cause and effect. But it may be 

 asked, what proof have we to offer in support of 

 this assertion, which is of such magnitude and 

 importance as to be the foundation of our proof 

 of all other assertions, and the means of enabling 

 us to convert a single case of observation into a 

 universal belief? 



There is no other proof to be offered for the 

 uniformity of nature than the unbroken experience 

 of the human race. Every age has found it so ; 

 and in the more recent times of human history, it 

 has been tested in every possible variety of ways, 

 and no valid exception has ever been recorded. 

 There was a time when men might entertain 

 doubts on the matter, or when the confirmation 

 was but limited, and the apparent exceptions 

 irreconcilable with the doctrine. But this time 

 has now gone by, and the principle has come to 

 be established upon a basis that seems impossible 

 to be shaken ; and all the future generations of 

 men will rest upon it with unswerving confidence. 

 Some have derived the proof of the principle from 

 an instinct in human nature, which leads us to 

 expect this uniformity ; but this is to rest upon a 

 most perilous assumption namely, that the native 

 instincts of men can correctly anticipate the laws 

 of the outer world an assumption, indeed, that 

 is far from true. The very same instinct which 

 leads us to expect uniformity in nature, also 

 prompts us to believe that all other men are like 

 ourselves ; that our experience is the experience 

 of the whole world ; and that what is at variance 

 with it must be false. It is the instinct that urges 

 the inhabitants of a tropical climate to denounce 

 as liars and impostors the people who assert that 

 water can become solid like glass. Such an 

 instinct is utterly untrustworthy, until corrected 

 by the observation of the actual world ; although 

 valuable as an impulse advancing in the same 

 general direction with the results of our experience. 



The laws of Causation, or the successions of 

 events established by nature, and invarinbly 

 adhered to, make the first and foremost subject 

 of inductive investigation. In this case the great 

 problem given for mankind to solve is to find 

 the effects of all causes, and the causes of all 

 effects. 



The general maxim of the uniformity of nature 

 does not always apply to the outward appearances 

 of things. A south wind brings rain one day and 

 drought another ; and in many other cases the 

 law of strict succession fails to hold good. The 

 reason of this is discovered by a very little ex- 

 amination ; the superficial phenomena of the 

 world, the things that prominently arrest our 

 attention, are not single trains of causation, but 

 mixtures of many different trains ; and the law 

 of uniformity does not necessarily hold good, 

 except in the simple and indivisible sequences of 

 phenomena and events. No doubt if a certain 

 number of causes acting together produce a 

 certain amount of effects, the very same combina- 

 tion will always produce like effects ; but it is not 

 easy to make sure that two given combinations 

 are really the same. In order to do so, we must 

 first become acquainted with the simple causes 

 one by one. Induction, therefore, in such a state 

 of things, is essentially a process of analysis, or 

 the separation of the complex threads of causa- 

 tion, with the view to determine the simple 

 threads ; and when we have once possessed 



