How then can a common observer test a physician in regard to this talent? If the observer were himself a physician, he could do this by watching him in his examinations of cases of disease. But as he is not, and is therefore ignorant of the subjects to be examined, he will fail in any attempt of this kind. He will be apt to commit, for example, this error. He sees that a physician makes a great many inquiries of his patients in regard to their complaints, and he may for this reason alone conclude that he is a nice observer. This minuteness of examination often gives a physician very unjustly this reputation; and in fact it is one of the most common tricks of the trade. There is often a great parade of questioning with very little true observation. A physician who is a skilful observer will learn more of a patient’s condition, by watching him as he lies in bed, and making a few inquiries, than another will by a multitude of questions; just as one man, who scarcely appears to look at anything as he passes through a street, may really observe and know more about the various objects in that street, than another man, who appears with eyes wide open to look at everything. A mere glance will sometimes reveal to the skilful observer the true nature of the case, when the unskilful have not been able to discover it with the most diligent examination of the symptoms. I will mention a single example. A man who was severely sick was attended by two physicians, who were somewhat at a loss in regard to the nature of his disease. Another physician, who was called in, before asking a single question, suspected from the posture of the patient that he had a hernia, in common language a rupture; and on examination this was found to be the case. I might mention some other errors, to which the inquirer would be liable, if he attempted to judge directly of the physician’s mode of examining disease, but it is not necessary. How then, the question recurs, shall he test the physician on the point under consideration? Let him see how the physician observes in regard to some subject, with which he himself is acquainted. He will discover in this way what his habits of observation are; and he may be sure, that these same habits mark his investigations of disease in the chamber of the sick. No man has different habits of observation for different subjects. Suppose that you have a curious article in your possession, and you have become acquainted with all the facts in regard to it. If you show it to several physicians, and observe the inquiries which they make in relation to it, you can discover the different characters of their minds, and may thus know how they observe and investigate disease. One of them asks perhaps but few questions, and some of those are irrelevant. He discovers but little in regard to the article, and you may be sure that he will never discover but little in regard to disease.