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31. This, in a 3ense, is the definition borrowed from the opinions of the, fifteen Judges in Daniel McNaughten's case who unanimously laid down that to establish a defence on the ground of insanity, it must be clearly proved that at the time of committing the act the accused was labouring under such a disease of the mind as not to know the nature and quality of the act he was doing, or if he did know it, he did not know he was doing what was wrong.

32. The learned Judges further pointed out that if a person labours under a delusion, he must be considered to be in the same situation as if the facts with respect to which the delusion exists were real, that is, the delusion must have reference to the fact in issue. Anything short of this standard, however much it may be regarded to be a case of insanity according to the medical science, is not insanity as recognized by law. The medical science has a long category of various degrees of abnormality which are thought to be insanity. They include idiocy, imbecility, feeble mindedness and subjectivity to stupor, exaltations, delusions, impulses, etc. Indeed, abnormality in one form or another is considered according to medical books as a species of insanity, but that is not the legal view.