physicians to mistake these local complications of delirium tremens for the disease itself. Another error, of a more directly practical character, which existed for a long time in relation to this same disease, will serve as another illustration of the influence of a partial view of facts, in leading to wrong conclusions. Dr. Sutton, one of the early authors on delirium tremens, asserted as the result of his observation, that the patient must sleep or die, and that opium in _large_ doses was the proper remedy to produce the sleep. This opinion was for a long time almost universally adopted, and practised upon. But the compared experience of _many_ observers has demonstrated this practice to be erroneous, and it is now very commonly given up by the profession. In examining disease, whether in a single case, or in groups of cases, it is essential to the formation of correct conclusions, that _all_ the symptoms be observed, and that their relative importance be duly estimated. Much error has arisen from a disregard of this plain truth. Take for example the observations of different individuals in regard to fever. Boerhaave, looking mainly at one class of symptoms, taught that fever was caused by a bad state of the blood; Cullen looking at another class of symptoms, considered fever to be an affection of the nervous system; Clutterbuck, fixing his eye upon another class of facts, was very sure that the cause of fever is always to be found in the brain; Broussais, directing his attention to the symptoms developed in another quarter of the system, asserted, that all fever arises from an inflammation of the mucous membrane of the stomach and of the upper portion of the intestines; Dr. Cooke of this country, narrowing his vision down to a certain set of symptoms, proclaimed that the primary cause of fever is a weakened action of the heart, producing an accumulation of blood in the venous system; and Samuel Thompson, following in his rude way the example of all previous theorizers on this subject, in taking into view but a part of the facts in the case, declared that fever is a battle between the cold and the heat, and that, if the cold conquer, the patient dies, and if the heat gain the victory, the patient lives.[29] It is thus that a disposition to form conclusions from a limited experience, and to take partial views of facts, leads to errors of opinion, and consequently errors of practice. I might multiply illustrations on this point, but it is not necessary.