Those are the states of the human intellect which have a distinct and separate existence, and which are capable of being described from their manifestations; there can be no intermediate state, and certainly no abstract or independant unsoundness: which, when it is acknowledged, must, on the one hand, be derived from insanity, or from idiotcy on the other. But the law has established a different system, and it is observed that “It seems to have been a very long time before those who had the administration of justice in this department, thought themselves at liberty to issue a commission, when the person was represented as not being ideot ex nativitate, as not being lunatic, but as being of unsound mind, importing by those words, the notion, that the party was in _some such state_, as was to be contradistinguished from idiotcy; and as he was to be contradistinguished from lunacy, and yet _such_ as made him a proper object of a commission, _in the nature_ of a commission to enquire of idiotcy, or a commission to enquire of lunacy.” Accepting this with great humility as the law, it is equally dutiful to endeavour to discover on what facts or experience it was established: and the only clue to this investigation is found in the words “_in some such state_,” as was neither idiotcy nor lunacy, but “such” as disqualified him from exercising the volition of an ordinary man, by an instrument “in the nature” of a commission applicable to ideot or lunatic. If this undefined unsoundness of mind, can thus dispossess the individual of his liberty, and of the use of his property, under the issuing of a commission, it performs sufficient; but it may be respectfully enquired, what would be the general opinion, or that of the commissioners of the College of Physicians, if a medical practitioner were to give a certificate to confine a person in a madhouse, declaring he was neither an ideot nor a lunatic, but of unsound mind?—And what attention would the judge and jury give to a physician in a criminal court who came to prove that a man who had committed murder was not responsible for the crime, because he was neither an ideot nor a lunatic, but of unsound mind; importing by these words that he was in _some such state_ as was to be contradistinguished from idiotcy, and as he was to be contradistinguished from lunacy? After having taken this view of the subject, which is the result of extensive experience in this department of the profession, and of diligent enquiry into the nature of the human mind; it appears to me, that the medical practitioner may safely and conscientiously infer unsoundness of mind, if such term be legally insisted on, whenever a morbid condition of intellect prevails, to an extent which deprives the mind of its natural and healthy offices, by producing an incapacity or inability in the individual to conduct himself and manage his affairs.