The constant and growing use of the Binet-Simon intelligence scale in public schools, institutions for defectives, reform schools, juvenile courts, and police courts is sufficient evidence of the intrinsic worth of the method. It is generally recognized, however, that the serviceableness of the scale has hitherto been seriously limited, both by the lack of a sufficiently detailed guide and by a number of recognized imperfections in the scale itself. The Stanford revision and extension has been worked out for the purpose of correcting as many as possible of these imperfections, and it is here presented with a rather minute description of the method as a whole and of the individual tests.

The aim has been to present the explanations and instructions so clearly and in such an untechnical form as to make the book of use, not only to the psychologist, but also to the rank and file of teachers, physicians, and social workers. More particularly, it is designed as a text for use in normal schools, colleges, and teachers’ reading-circles.

While the use of the intelligence scale for research purposes and for accurate diagnosis will of necessity always be restricted to those who have had extensive training in experimental psychology, the author believes that the time has come when its wider use for more general purposes should be encouraged.

However, it cannot be too strongly emphasized that no one, whatever his previous training may have been, can make proper use of the scale unless he is willing to learn the method of procedure and scoring down to the minutest detail. A general acquaintance with the nature of the individual tests is by no means sufficient.

Perhaps the best way to learn the method will be to begin by studying the book through, in order to gain a general acquaintance with the tests; then, if possible, to observe a few examinations; and finally to take up the procedure for detailed study in connection with practice testing. Twenty or thirty tests, made with constant reference to the procedure as described in PartII, should be sufficient to prepare the teacher or physician to make profitable use of the scale.

The Stanford revision of the scale is the result of a number of investigations, made possible by the coÖperation of the author’s graduate students. Grateful acknowledgment is especially due to Professor H.G. Childs, Miss Grace Lyman, Dr.George Ordahl, Dr.Louise Ellison Ordahl, Miss Neva Galbreath, Mr.Wilford Talbert, Mr.J. Harold Williams, and Mr.Herbert E. Knollin. Without their assistance this book could not have been written.

Stanford University,
April, 1916.