LAWS OF MIND. 433 



peculiarly designated as mental : and by the laws of mind, I 

 mean the laws according to which those feelings generate one 

 another. 



2. All states of mind are immediately caused either by 

 other states of mind, or by states of body. When a state of 

 mind is produced by a state of mind, I call the law concerned 

 in the case, a law of Mind. When a state of mind is produced 

 directly by a state of body, the law is a law of Body, and 

 belongs to physical science. 



With regard to those states of mind which are called sen- 

 sations, all are agreed that these have for their immediate 

 antecedents, states of body. Every sensation has for its proxi- 

 mate cause some affection of the portion of our frame called 

 the nervous system ; whether this affection originate in the 

 action of some external object, or in some pathological condi- 

 tion of the nervous organization itself. The laws of this portion 

 of our nature the varieties of our sensations, and the physical 

 conditions on which they proximately depend manifestly be- 

 long to the province of Physiology. 



Whether the remainder of our mental states are similarly 

 dependent on physical conditions, is one of the vexata ques- 

 tiones in the science of human nature. It is still disputed 

 whether our thoughts, emotions, and volitions are generated 

 through the intervention of material mechanism; whether we 

 have organs of thought and of emotion, in the same sense in 

 which we have organs of sensation. Many eminent physio- 

 logists hold the affirmative. These contend, that a thought 

 (for example) is as much the result of nervous agency, as a 

 sensation : that some particular state of our nervous system, in 

 particular of that central portion of it called the brain, inva- 

 riably precedes, and is presupposed by, every state of our con- 

 sciousness. According to this theory, one state of mind is 

 never really produced by another : all are produced by states 

 of body. When one thought seems to call up another 

 by association, it is not really a thought which recals a 

 thought; the association did not exist between the two 

 thoughts, but between the two states of the brain or nerves 

 VOL. ii. 28 



