The law punishes negligence no less than want of skill. It is undoubtedly true that the physician is the best judge of the degree of attention which any case requires. Nor is it in the omission to make a given number of visits that negligence resides, but whenever any important step in the treatment of disease is neglected, or any important stage of it overlooked, which might have been used for the benefit of the patient, then it may be averred that the physician has been guilty of negligence, however assiduous he may otherwise have been at different periods of his treatment. Skill and diligence may be considered, therefore, as indissolubly associated, since skill judges of the measure of diligence required and also furnishes the latter with the eyes of observation and the hands of execution; while diligence on her part gives cumulative power to skill, and leaves no link wanting in the continuous train of treatment [141]. The measure of skill which a physician is bound to exercise is not affected by his refusal of the proffer of assistance from other medical men [142]. The Court said that such a refusal is no more than an implied declaration of ability to treat the case properly. By assuming and continuing the charge of the patient, the physician is under an obligation to exercise a degree of skill which is neither increased or diminished by such refusal. In considering the skill and knowledge of a practitioner regard must be had to the school to which he professes to |64| belong; and where there is no particular system established or favoured by law, and no system is prohibited, every physician is expected to practise according to his professed and avowed system. A botanic physician is to be gauged according to the botanic system, and a homœopathic physician by the homœopathic system: so if a botanic doctor, or a homœopathist, is sued for malpractice he may free himself from blame by showing that his practice was according to the rules of the school which he professed and was known to follow, and a departure from the received canons of his system will be taken as a want of ordinary skill. But the jury is not to judge by determining which school in their own view is best [143]. A sign or other proof that one actually practises physic or surgery is _prima facie_ evidence of his professional character [144]. And when a physician’s skill is at issue he may adduce evidence to prove the existence of such general skill on his part, irrespective of the particular case as to which the question arises; and he may show this by the testimony of those in his profession who can speak from personal knowledge of his practice [145]. The possession of a medical diploma is _prima facie_ of ordinary skill. But of course it must be shown that the college from which it emanated had authority to grant degrees in medicine [146].