It has been said that all sciences pass through three stages, that of philosophic anticipation, that of detailed observation, and that of careful generalization. The science of immunology is now in the second stage, and is engaged in gaining a mastery of the facts upon which reliable generalizations may in the future be based. Knowledge of the details of the science is increasing apace, and day by day the sure foundations are being laid of a permanent and well established theory.
Annually we meet to exchange with one another the fruits of the year's labors, and so to widen and deepen the stream of our knowledge. But, of necessity, we deal with sharply circumscribed problems, because we wish to give one another only such things as we have thoroughly proved and tested. This tacit, but general, law of these meetings was wisely broken last year in Dr. Jobling's presidential address, which aspired to give a broad and critical review of one very important aspect of immunological study.
Presidential address at the fourth annual meeting of the American Association of Immunologists, held at New York City, April 5 and 6, 1917.