The motive back of these tests is well expressed in the following paragraph which was also used as material for a test of logical memory:
"Tests such as we are now making are of value both for the advancement of science and for the information of the student who is tested. It is of importance for science to learn how people differ and on what factors these differences depend. If we can disentangle the complex influences of heredity and environment we may be able to apply our knowledge to guide human development. Then it is well for each of us to know in what way he differs from others. We may thus in some cases correct defects and develop aptitudes which we might otherwise neglect."
The nature of these Columbia tests and the method of recording and reporting them are indicated in the forms which were printed and used for this special purpose. (Samples of these are given in the Appendix.) They are given here not so much for the sake of the enumeration of the tests, since many of these are no longer in common use, but because of their historic interests for vocational psychology and because of the general plan outlined in them. In general this plan is that of accumulating measurements of a large number of individuals and thus showing each one how he compares with the normal or average, or where he stands in the general curve of distribution of the members of the group. These tests were applied to the same individuals on their entrance to and their graduation from college, in order to indicate changes that might have been made during the intervening period.
Especially interesting also are other blanks containing additional data, such as age, health, physical characteristics, physiognomic features, enumeration of stigmata, etc. In addition to the tests and measurements, the examiner, both before and after the interview, recorded his general impression of the individual, in the terms indicated on the blank form. We shall have occasion to refer to these judgments of general impression in more detail when we come to consider the use of the interview and the testimonial in vocational psychology. Account was also taken of the gymnasium records of the student, as to nationality, birth, parentage, habits, health, etc.