LAWS OF MIND. 593 



But we can not perceive, in so apparently simple a feeling as our percep- 

 tion of the shape of an object by the eye, all that multitude of ideas de- 

 rived from other senses, without which it is well ascertained that no such 

 visual perception would ever have had existence ; nor, in our idea of Ex- 

 tension, can we discover those elementary ideas of resistance, derived from 

 our muscular frame, in which it has been conclusively shown that the idea 

 originates. These, therefore, are cases of mental chemistry; in which it is 

 proper to say that the simple ideas generate, rather than that they compose, 

 the complex ones. 



With respect to all the other constituents of the mind, its beliefs, its ab- 

 struser conceptions, its sentiments, emotions, and volitions, there are some 

 (among whom are Hartley and the author of the Analysis) who think that 

 the whole of these are generated from simple ideas of sensation, by a chem- 

 istry similar to that wTiich we have just exemplified. These philosophers 

 have made out a great part of their case, but I am not satisfied that they 

 have established the whole of it. They have shown that there is such a 

 thing as mental chemistry ; that the heterogeneous nature of a feeling A, 

 considered in relation to B and C, is no conclusive argument against its 

 being generated from B and C. Having proved this, they proceed to 

 show, that where A is found, B and C were, or may have been present, and 

 why, therefore, they ask, should not A have been generated from B and 

 C ? But even if this evidence were carried to the highest degree of com- 

 pleteness which it admits of; if it were shown (which hitherto it has not, 

 in all cases, been) that certain groups of associated ideas not only might 

 have been, but actually were, present whenever the more recondite mental 

 feeling was experienced ; this would amount only to the Method of Agree- 

 ment, and could not prove causation until confirmed by the more conclu- 

 sive evidence of the Method of Difference. If the question be whether 

 Belief is a mere case of close association of ideas, it would be necessary 

 to examine experimentally if it be true that any ideas whatever, provided 

 they are associated with the required degree of closeness, give rise to be- 

 lief. If the inquiry be into the origin of moral feelings, the feeling for ex- 

 ample of moral reprobation, it is necessary to compare all the varieties of 

 actions or states of mind which are ever morally disapproved, and see 

 whether in all these cases it can be shown, or reasonably surmised, that the 

 action or state of mind had become connected by association, in the disap- 

 proving mind, with some particular class of hateful or disgusting ideas; 

 and the method employed is, thus far, that of Agreement. But this is not 

 enough. Supposing this proved, we must try further by the Method of 

 Difference, whether this particular kind of hateful or disgusting ideas, 

 when it becomes associated with an action previously indifferent, will ren- 

 der that action a subject of moral disapproval. If this question can be 

 answered in the affirmative, it is shown to be a law of the human mind, 

 that an association of that particular description is the generating cause of 

 moral reprobation. That all this is the case has been rendered extremely 

 probable, but the experiments have not been tried with the degree of pre- 

 cision necessary for a complete and absolutely conclusive induction.* 



It is further to be remembered, that even if all which this theory of 



* In the case of the moral sentiments the place of direct experim^t is to a considerable 

 extent supplied by historical experience, and we are able to trace with a tolerable approach to 

 certainty the particular associations by which those sentiments are engendered. Tiiis has 

 been attempted, so far as respects the sentiment of justice, in a little' woik by the present au- 

 thor, entitled Utilitarianism, 



38 



