> 



PEEFACE TO THE FIEST EDITION. 



This book makes no pretence of giving to the Avorld a new theory 

 of the intellectual operations. Its claim to attention, if it possess 

 any, is grounded on the fact that it is an attempt not to supersede, 

 but to embody and systematise, the best ideas which have been 

 either promulgated on its subject by speculative writers, or con- 

 formed to by accurate thinkers in their scientific inquiries. 



To cement together the detached fragmeuts of a subject never yet 

 treated as a whole ; to harmonise the true portions of discordant 

 theories, by supplying the links of thought necessary to connect 

 them, and by disentangling them from the errors with which they 

 are always more or less interwoven ; must necessarily require a con- 

 siderable amount of original specnlation. To other originality than 

 this, the present work lays no claim. In the existing state of the 

 cultivation of the sciences, there would be a very strong presumption 

 against any one who should imagine that he had eftected a revolution 

 in the theory of the investigation of truth, or added any funda- 

 mentally new process to the practice of it. The improvement which 

 remains to be etiected in the metliotls of philosophising (and tliQ 

 author believes that they have much need of improvement) can only 

 consist in performing more systematically and accurately operations; 

 with which, at least in their elementary form, the human intellect in 

 some one or other of its employments is already familiar. 



In the portion of the work which treats of Ratiocination, the 

 author has not deemed it necessary to enter into technical details 

 which may be obtained in so perfect a shape from the existing 

 treatises on what is termed the Logic of the Schools. In the con- 

 tempt entertained by many modern philosophers for the syllogistic 

 art, it will be seen that he by no means participates ; though the 

 scientific theory on Avhich its defence is usually rested appears to him 

 erroneous : and the view which he has suggested of the nature and 

 functions of the Syllogism may, perhaps, afford the means of con- 



