From this brief recapitulation of the important influences affecting research in medicine, only one conclusion is deducible; that although the individual will continue to be the most significant factor in the situation, it is unquestionable that his perception will be constantly stimulated, his imagination quickened and his hands aided, by the opportunities, ideals and facilities of the laboratory. In the laboratory only can "the prepared mind" of Pasteur's adage ("In the fields of observation chance favors only the prepared mind") be properly fostered. It is in the laboratory, and under this term I include the properly conducted hospital as the laboratory of clinical medicine, that medicine keeps in close touch with new discoveries in physics, chemistry and biology, the second of the three important factors we have discussed. The situation in regard to the auxiliary sciences has not changed since the time of Liebig, Müller and Virchow. The investigator in the laboratory and the investigator in the hospital still look to these sciences for assistance and eagerly apply the discoveries in each of these his own problems. The result is a decided advantage to medicine, not only in that this revivifying and suggestive influence leads to accelerated progress in the science and art of medicine, but also in that it directly influences the health and therefore the welfare, commercial and social, of the community.
This brings us to the fourth factor which has influenced medical research in the past and should—indeed must—continue to be an ever-increasing influence in the future—the desire to ameliorate social condition, by diminishing the causes of physical and mental ills. This, in a word, is the desire for social service; the impulse which actuated all of Pasteur's work, and which he himself expressed as the desire to contribute "in some manner to the progress and welfare of humanity." It is not sufficient that the individual as an investigator should be actuated only by his ambition and his investigations, or alone by his desire for exact abstract knowledge. If medical research is to be a vitalizing, reforming, uplifting factor, not only for the practise of medicine, but for the good of the community at large, then the whole man must be interested, heart and soul, not only in the technical and abstract results of his problems, but in their practical applications to medical and social conditions. What does this mean for medical research? That the laboratory shall be not only the brains, but the hands, of the community! It must recognize not only the problems of the community, but, solving the technical aspects of these problems, must demonstrate how they are to be met and cared for. In short, the investigator in medicine must be stirred by not only an abstract interest in human ills, but a direct interest in the problems, prophylactic or therapeutic, hygienic or social, of the community, with all its differen-