1 68 NATURE AND MAN. 



mediate seat of these impulses, Dr. Todd agrees with us in 

 locating in the sensory ganglia; but he does not seem to us 

 sufficiently to recognize the participation of the cerebrum in 

 emotional states. A simple feeling of pleasure or pain excited 

 by a sensation, and tending to react directly upon the muscular 

 system, cannot be correctly termed an emotion ; for this last 

 involves an idea, which, though originally springing from a 

 sensation, at last comes to be quite independent of external 

 stimuli. But the idea is not emotional so long as it is a state 

 of simple consciousness : it must be associated with a pleasur 

 able or painful feeling, in order that it may become so ; and then, 

 if strongly excited, it may act at once through the automatic 

 centres, without any effort of the will. In an emotional action, 

 then, we believe the impulse to be formed in the sensorial centres, 

 so that it so far resembles an instinctive movement; but this im 

 pulse derives its force rather from a cerebral idea than from an 

 external sensation ; and its influence, if not exerted downwards 

 through the motor apparatus, is transmitted back again to the 

 cerebrum, so as to modify the course of the intellectual opera 

 tions, and to supply motives to the will. 



