For those venerable authorities of the law, who have preceded your Lordship in this department of the administration of justice, I feel impressed with the utmost deference and respect; and these grateful sentiments will be rendered more intense whenever their reasons are promulgated. Medical practitioners, who have devoted their lives to the consideration and treatment of insanity, are disposed to doubt concerning the existence of any intrinsic or positive unsoundness of mind, as contra-distinguished from idiotcy and lunacy. Those who have accumulated the largest sum of experience in disorders of the intellect, have viewed the various forms under which they are manifested, as equally conducing to render an individual incapable of conducting himself and managing his affairs, whether the mental affection be termed madness, melancholy, insanity, mental derangement, non compos mentis, idiotcy, or lunacy; and, if it were necessary, a more ample catalogue might be introduced. Physicians may, perhaps, be advantageously occupied in establishing nice shades of difference in the symptoms of mental disorder; and, if we do not already possess sufficient, may create new terms expressive of these modifications: and such extension of the nosological volume may have its practical utility: but the lawyer can have no interest in such speculations, he only looks to the medical evidence to demonstrate the existence of that _morbid_ condition of intellect that renders the individual incompetent to conduct himself in society, and to manage his affairs.