When invalids have nothing to occupy their time and attention, their thoughts become centered upon themselves, and they grow morbid and irritable. Many times they dwell upon their bad feelings until they think themselves much worse than they really are and wholly unable to do anything. (MH 239.1) MC VC

In all these cases well-directed physical exercise would prove an effective remedial agent. In some cases it is indispensable to the recovery of health. The will goes with the labor of the hands; and what these invalids need is to have the will aroused. When the will is dormant, the imagination becomes abnormal, and it is impossible to resist disease. (MH 239.2) MC VC