12 NATURE AND DESIGN OF THIS WORK. [CHAP. I. 



1 1 . Beside the general statement of the principles of the 

 above method, this treatise will exhibit its application to the 

 analysis of a considerable variety of propositions, and of trains of 

 propositions constituting the premises of demonstrative argu- 

 ments. These examples have been selected from various writers, 

 they differ greatly in complexity, and they embrace a wide range 

 of subjects. Though in this particular respect it may appear to 

 some that too great a latitude of choice has been exercised, I do 

 not deem it necessary to offer any apology upon this account. 

 That Logic, as a science, is susceptible of very wide applications 

 is admitted ; but it is equally certain that its ultimate forms and 

 processes are mathematical. Any objection a priori which may 

 therefore be supposed to lie against the adoption of such forms 

 and processes in the discussion of a problem of morals or of ge- 

 neral philosophy must be founded upon misapprehension or false 

 analogy. It is not of the essence of mathematics to be conversant 

 with the ideas of number and quantity. Whether as a general 

 habit of mind it would be desirable to apply symbolical processes 

 to moral argument, is another question. Possibly, as 1 have 

 elsewhere observed,* the perfection of the method of Logic may 

 be chiefly valuable as an evidence of the speculative truth of its 

 principles. To supersede the employment of common reasoning, 

 or to subject it to the rigour of technical forms, would be the last 

 desire of one who knows the value of that intellectual toil and 

 warfare which imparts to the mind an athletic vigour, and teaches 

 it to contend with difficulties, and to rely upon itself in emer- 

 gencies. Nevertheless, cases may arise in which the value of a 

 scientific procedure, even in those things which fall confessedly 

 under the ordinary dominion of the reason, may be felt and ac- 

 knowledged. Some examples of this kind will be found in the 

 present work. 



12. The general doctrine and method of Logic above ex- 

 plained form also the basis of a theory and corresponding method 

 of Probabilities. Accordingly, the development of such a theory 

 and method, upon the above principles, will constitute a distinct 

 object of the present treatise. Of the nature of this application 

 it may be desirable to give here some account, more especially as 



* Mathematical Analysis of Logic. London : G. Bell. 1847. 



