BOOK II.] INSTANCES OF DIVORCE. 615 



inclosed within another flame, and not exposed to the resisting 

 force of the air. 



Let this suflSce for the instances of the cross. We have dwelt 

 the longer upon them in order gradually to teach and accustom 

 mankind to judge of nature by these instances, and enlightening 

 experiments, and not by probable reasons.' 



aXXVII. Wc will treat of the instances of divorce as the 

 fifteenth of our prerogative instances. They indicate the sepa- 

 ration of natures of the most common occurrence. They dilier, 

 however, from those subjoined to the accompanying instances; 

 for the instances of divorce point out the separation of a particular 

 nature from some concrete substance with which it is usually 

 found in conjunction, whilst the hostile instances point out the 

 total separation of one nature from another. They differ, also, 

 from the instances of the cross, because they decide nothing, but 

 only inform us that the one nature is capable of being separated 

 from the other. They are of use in exposing false forms, and 

 dissipating hasty theories derived from obvious facts ; so that 

 they add ballast and weight, as it were, to the understanding. 



For instance, let the required natures be those four which 



* These instances, which Bacon seems to consider as a great discovery, 

 are nothing more than disjunctive propositions combined with dilem- 

 mas. In proposing to explain an effect, we commence with the enu- 

 meration of the different causes which seem connected with its produc- 

 tion ; then with the aid of one or more dilemmas, we eliminate each 

 of the phenomena accidental to its composition, and conclude with 

 attributing the effect to the residue. For instance, a certain phe- 

 nomenon (a) is produced either by phenomenon (b) or phenomenon (c) ; 

 but C cannot be the cause of a, for it is found in D, E, F, neither of 

 which are connected with a. Then the true cause of phenomenon (a) 

 must be phenomenon (b). 



This species of reasoning is liable to several paralogisms, against 

 which Bacon has not guarded his readers, fiom the very fact that he 

 stumbled into them unwittingly himself. The two principal ones are 

 false exclusions and defective enumerations. Bacon, in his survey of 

 the causes which are able to concur in producing the phenomena of 

 the tides, takes no account of the periodic melting of the Polar ice, or 

 the expansion of water by the solar heat : nor does he fare better in 

 his exclusions. For the attraction of the planets and the progression 

 and retrogi-ade motion communicated by the earth's diurnal revolution, 

 can plainly affect the sea together, and have a simultaneous influence 

 on its surface. 



Bacon is hardly just or consistent in his censure of Ramus ; the end 

 of whose dichotomy was only to render reasoning by dilemma, and 

 crucial instances, more certam in their results, by reducing the divisions 

 which composed their parts to two sets of contradictory propositions. 

 The affirmative or negative of one would then necessarily have led to 

 the acceptance or rejection of the other. Ed. 



