Again, it is not always the case that the imaginary acts of the will are not executed during sleep; and hence it would follow from Mr. Stewart’s argument that the power of the will over the body is not then suspended. Assuming for the moment that the volitions of sleep are real, as Mr. Stewart supposes; if it can be shown that they are satisfactorily performed, it results from his line of reasoning that the will has power over the body during sleep. Every one who has ever dreamed has at times had his will carried out to his entire satisfaction. He has ridden horses when pursued, and has urged them forward with whip and spur so as to escape from his enemies. Or he has executed the most surprising feats both with his mind and body, and has performed voluntary deeds which have excited the admiration of all beholders. Such acts are of course entirely the product of the imagination, and all the volitions which accompany them have no firmer basis than the unbridled fancy; but, according to Mr. Stewart, they would be evidence of the power of the will over the body,--a power which in reality does not exist; not, however, as Mr. Stewart supposes from any impediments in the nerves or muscles, but because it is never exerted. So far as relates to movements performed during sleep, such as turning in bed and assuming more comfortable positions, they have nothing whatever to do with the will. They are dependent upon the action of the spinal cord, an organ that is never at rest, and the functions of which were not known as well when Dr. Darwin and Mr. Stewart wrote as they are now. The same is true of more complex and longer-continued actions, such as those already mentioned of individuals riding on horseback, or even walking, during sleep. Cabanis[61] contends that the will is not entirely suspended during sleep; but, as will be perceived from the following quotation, he bases his argument upon the fact that movements are produced which he attributes erroneously to the action of the will, but which, like those previously referred to, are accomplished by the agency of the spinal cord. He says, speaking of the instances of persons walking while asleep: