which they have been taught by ear; but they are incapable of comprehending what they repeat.
There is a degree of intellect, although mean, when compared with superior minds, which will enable a human being to take charge of himself, and transact his affairs; and there is also an inferior degree, which incapacitates him from the performance of those offices: and patient examinations at repeated interviews will enable the observer to ascertain his competency, and to afford a satisfactory evidence of the state of his mind: for the mind of every man may be gauged, both as to its acquirements and capacity. By imbecility, therefore, which may be either natural, or induced by a variety of causes, it will be seen, that I mean a state or degree of mental incapacity equivalent to ideotcy, a degree, which renders him incompetent to the
management of himself and affairs:—and which degree, by observation and enquiry, may always be ascertained. This degree, satisfactorily measured, does, in my own opinion, amount to unsoundness of the individual’s mind: as it includes all the mental evidences which constitute unsoundness.
Connected with these subjects, there is a point of considerable importance, and of frequent occurrence, which yet remains to be examined, and with which the present essay will conclude: namely, the state of mind, under which, a person may legally dispose of his property by will. Medical practitioners are often called upon to attest the competence or incapacity of particular persons to the performance of this act, which requires a state of disposing mind. In many instances it is deferred to that extremity of bodily disease when recovery is hopeless. To urge its
propriety or necessity at an earlier period, often excites alarm or despondency, and such state of feeling, the medical attendant, in many disorders, is unwilling to excite. As a person of liberal education, and from the enquiries he has made during his attendance on the patient, he is justly presumed a proper judge of his competence to dispose. This instrument is termed a will, which does not simply imply an act of volition, but the volition of a sound or sane mind; because a lunatic, of all men, is most the creature of volition. The same conditions of intellect which have been heretofore enumerated, as exempting him from punishment, and disqualifying him from the management of his affairs, would, as far as a medical opinion may prevail, equally disable him from disposing of his property: such disposal involving the most important part of its management.
There is great, perhaps insuperable, difficulty in considering this subject in a general point of view. It is presumed, that no person, actually under a commission of lunacy, could legally dispose of his property by will, because such instrument confides the management of his affairs to others. But in the judgment before cited, and where the law is expounded by the highest and most competent authority, it appears, that the legal definition of a lunatic, implies a person interchangeably visited by insanity and reason. “The question whether he was a lunatic, being a question, admitting in the solution of it of a decision, that imputed to him at one time an extremely sound mind, but at other times an occurrence of insanity, with reference to which, it was necessary to guard his person and his property by a commission issuing.”
In the insane mind, these parentheses of reason, have been technically denominated a lucid interval, which in a former work[102:A] I have endeavoured to explain, as far as such state becomes obvious to the medical practitioner. Its legal force I do not pretend to calculate. According to the legal interpretation of a lunatic, he ought, in common justice, at those bright periods when he possesses an extremely sound mind, to be lawfully allowed the free and valid exercise of his volition. But having noticed in the work above mentioned that the term interval is extremely indefinite, as applied both to time and space, it is the province of the law to define its duration and extent. As a constant observer of this disease for more than twenty-five years, I cannot affirm that the lunatics with whom I have had daily
intercourse, have manifested these alternations of insanity and reason. They may at intervals become more tranquil, and less disposed to obtrude their distempered fancies into notice. For a time their minds may be less active, and the succession of their thoughts consequently more deliberate;—they may endeavour to effect some desirable purpose, and artfully conceal their real opinions, but they have not abandoned or renounced their distempered notions. It is as unnecessary to repeat that a few coherent sentences do not constitute the sanity of the intellect, as that the sounding of one or two notes of a keyed instrument, could ascertain it to be in tune. To establish its sanity it must be assayed by different tests, and it must be detected to be as lucid on the subject of those delusions, which constituted its insanity, as on topics of a trivial nature. But the law alone must determine whether it will