We say with assurance that the mind rules the body, we feel that the spirit in some way overshadows and includes the mind.

Yet if this were really true the spirit--that is, the will--should have power against bodily pain, but not against moral suffering except with some help from a higher source.
But it is otherwise.

If the will of ordinary human beings could hypnotise the body against material sensation, the credit due to those brave believers in all ages who have suffered cruel torments for their faith would be singularly diminished.

If the mind could dominate matter by ordinary concentration of thought, a bad toothache should have no effect upon the delicate imagination of the poet, and Napoleon would not have lost the decisive battle of his life by a fit of indigestion, as has been asserted.
On the other hand, there was never yet a man of genius, or even of great talent, who was not aware that the most acute moral anguish can be momentarily forgotten, as if it did not exist for the time, by concentrating the mind upon its accustomed and favourite kind of work.
Johnson wrote _Rasselas_ to pay for the funeral of his yet unburied mother, and Johnson was a man of heart if ever one lived; he could not have written the book if he had had a headache.

Saints and ascetics without end and of many persuasions have resorted to bodily pain as a means of deadening the imagination and exalting the will or spirit.