VESANI^E. 511 



the exercise of it they will follow the same train of associa- 

 tions. 



" Notwithstanding this similarity, there may be a great di- 

 versity in the judgments of men, from want of perceptions, from 

 some difference in perceptions, especially complex, from a 

 great difference in the number of relations marked, and their 

 exactness, and lastly from the number and variety of associa- 

 tions ; whence a different state of the mind in different indivi- 

 duals, or at different times. 



" But at the same time, there are so many circumstances of 

 human life in common to all men, that there must be so much 

 similarity as 'to establish a common sense , that is, perceptions, 

 relations, associations, and judgments, in which all agree; and 

 when any particular man differs from all others in these re- 

 spects, we say, he is not in his senses, but insane." 



MDXXXII. With this mistaken judgment of relations 

 there is frequently joined some false perception of external ob- 

 jects, without any evident fault in the organs of sense, and 

 which seems therefore to depend upon an internal cause ; that 

 is, upon the imagination, arising from a condition in the brain, 

 presenting objects which are not actually present. Such false 

 perceptions must necessarily occasion a delirium, or an errone- 

 ous judgment, which is to be considered as the disease. 



MDXXXII I. Another circumstance, commonly attending 

 delirium, is a very unusual association of ideas. As, with re- 

 spect to most of the affairs of common life, the ideas laid up in 

 the memory are, in most men, associated in the same manner ; 

 so a very unusual association, in any individual, must prevent 

 his forming the ordinary judgment of those relations which are 

 the most common foundation of association in the memory : and, 

 therefore, this unusual, and commonly hurried association of 

 ideas, usually is, and may be considered as a part of delirium. 

 In particular, it may be considered as a certain mark of a gene-, 

 ral morbid affection of the intellectual organs, it being an in- 

 terruption or perversion of the ordinary operations of memory, 

 the common and necessary foundation of the exercise of judg- 

 ment. 



MDXXXIV. A third circumstance attending delirium, is 

 an emotion or passion, sometimes of the angry, sometimes of 



