On September 15, 1906, the Training School for Backward and Feeble-minded Children at Vineland, New Jersey, opened a laboratory and a Department of Research for the study of feeble-mindedness.

A beginning was made in studying the mental condition of the children who lived in the Institution, with a view to determining the mental and physical peculiarities of the different grades and types, to getting an accurate record of what deficiencies each child had and what he was capable of doing, with the hope that in time these records could be correlated with the condition of the nervous system of the child, if he should die while in the Institution and an autopsy should be allowed.

As soon as possible after the beginning of this work, a definite start was made toward determining the cause of feeble-mindedness. After some preliminary work, it was concluded that the only way to get the information needed was by sending trained workers to the homes of the children, to learn by careful and wise questioning the facts that could be obtained. It was a great surprise to us to discover so much mental defect in the families of so many of these children. The results of the study of more than 300 families will soon be published, showing that about 65 per cent of these children have the hereditary taint.

The present study of the Kallikak family is a genuine story of real people. The name is, of course, fictitious, as are all of the names throughout the story. The results here presented come after two years of constant work, investigating the conditions of this family.

Some readers may question how it has been possible to get such definite data in regard to people who lived so long ago.

A word of explanation is hence in order. In the first place, the family itself proved to be a notorious one, so the people, in the community where the present generations are living, know of them; they knew their parents and grandparents; and the older members knew them farther back, because of the reputation they had always borne. Secondly, the reputation which the Training School has in the State is such that all have been willing to coÖperate as soon as they understood the purpose and plan of the work. This has been of great help. Thirdly, the time devoted to this investigation must not be overlooked. A hasty investigation could never have produced the results which we have reached. Oftentimes a second, a third, a fifth, or a sixth visit has been necessary in order to develop an acquaintance and relationship with these families which induced them gradually to relate things which they otherwise had not recalled or did not care to tell. Many an important item has been gathered after several visits to these homes. 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 Chapter IV.

I am also greatly indebted to my assistants in the laboratory, for help in preparing the charts, keeping the records, and correcting manuscript and proof.

To Superintendent Edward R. Johnstone, whose wisdom and foresight led to the establishment of this Department of Research, whose help, sympathy, and encouragement have been constant throughout the work of preparing this study, the thanks and gratitude of the entire group of readers who find in these facts any help toward the solution of the problems that they are facing, are due.

HENRY H. GODDARD.

Vineland, N.J., September, 1912.