THE ORGANICAL SCIENCES. 421 



creatures. It will be sufficient, if we follow a few 

 of the lines of such researches, which may be consi- 

 dered as examples of the whole. We see that life 

 is accompanied and sustained by many processes, 

 which at first offer themselves to our notice as 

 separate functions, however they may afterwards be 

 found to be connected and identified ; such are 

 feeding, digestion, respiration, the action of the 

 heart and pulse, generation, perception, voluntary 

 motion. The analysis of any one of these functions 

 may be pursued separately. And since in this, as 

 in all genuine sciences, our knowledge becomes real 

 and scientific, only in so far as it is verified in par- 

 ticular facts, and thus established in general propo- 

 sitions, such an original separation of the subjects 

 of research is requisite to a true representation of 

 the growth of real knowledge. The loose hypo- 

 theses and systems, concerning the connexion of 

 different vital faculties and the general nature of 

 living things, which have often been promulgated, 

 must be excluded from this part of our plan. We 

 do not deny all value and merit to such specula- 

 tions; but they cannot be admitted in the earlier 

 stages of the history of physiology, treated of as an 

 inductive science. If the doctrines so propounded 

 have a solid and permanent truth, they will again 

 come before us when we have travelled through the 

 range of more limited truths, and are prepared to 

 ascend with security and certainty into the higher 

 region of general physiological principles. If they 



