Chapter IV

will throw still more light on the method used.

If the reader is inclined to the view that we must have called a great many people feeble-minded who were not so, let him be assured that this is not the case. On the contrary, we have preferred to err on the other side, and we have not marked people feeble-minded unless the case was such that we could substantiate it beyond a reasonable doubt. If there was good reason to call them normal, we have so marked them. If not, and we are unable to decide in our own minds, we have generally left them unmarked. In a few cases, we have marked them normal or feeble-minded, with a question mark. By this is meant that we have studied the case and after deliberation are still in doubt, but the probabilities are “N” or “F” as indicated. The mere fact of the doubt shows, however, that they are at least border-line cases.

To the scientific reader we would say that the data here presented are, we believe, accurate to a high degree. It is true that we have made rather dogmatic statements and have drawn conclusions that do not seem scientifically warranted from the data. We have done this because it seems necessary to make these statements and conclusions for the benefit of the lay reader, and it was impossible to present in this book all of the data that would substantiate them. We have, as a matter of fact, drawn upon the material which is soon to be presented in a larger book. The reference to Mendelism is an illustration of what we mean. It is, as it is given here, meager and inadequate, and the assumption that the given law applies to human heredity is an assumption so far as the data presented are concerned. We would ask that the scientist reserve judgment and wait for the larger book for the proof of these statements and for an adequate discussion of Mendelism in relation to the problem.

The necessary expense for this study, as well as for all of the work of the Research Laboratory, has been met by voluntary contributions from philanthropic men and women, who believe that here is an opportunity to benefit humanity, such as is hardly equaled elsewhere.

We take this means of expressing to them our deep appreciation of their sympathy and generosity. I wish also to make special mention of the indefatigable industry, wisdom, tact, and judgment of our field workers who have gathered these facts and whose results, although continually checked up, have stood every test put upon them as to their accuracy and value.

The work on this particular family has been done by Elizabeth S. Kite, to whom I am also indebted for practically all of