Measure Your Mind: The Mentimeter and How to Use It

by Marion Rex Trabue; Frank Parker Stockbridge

The intelligent reader has by this time begun to see for himself some of the possibilities opened up by the use of scientific mental tests, and to perceive their applicability in a wide diversity of fields. In later chapters specific examples of such applications are given in detail, and suggestions offered for still other uses of the tests which are contained in this book.

The usefulness of all mental tests, whether those which are offered in this volume under the general title of “The Mentimeter,” or others that may be set up with equal scientific precision, depends upon, or at least is greatly enhanced by, the most complete understanding of the underlying principles on the part of the person who undertakes to apply them. The purpose of this and the next three succeeding chapters is to make these principles so plain that by the time the reader has reached the tests themselves he will have a perfectly clear understanding, not only of what the Mentimeter tests are but of why they have been put into the form in which he finds them, and of how their use will enable him to gauge human intelligence and capacity with a greater degree of accuracy than he has found possible by other means. If, perchance, psychologists find in this volume much that is to them elementary, it should be kept in mind that it is only through the widest possible spread of sound understanding of psychological principles that the wider application of them in the ordinary walks of life can be brought about. That, the authors take it, is the great end toward which scientific psychologists are aiming, and that is the aim of this book.

The general purpose of psychological tests is to determine how individuals compare with one another in mental capacity, or with standards based upon the capacities of individuals known to possess certain qualities. Thus, it may be desirable, as it frequently is, to determine the relative abilities of the individuals of a certain group, like a school or college class, clerks employed in a similar form of work, a number of applicants for a certain position for which only the most capable among the candidates is desired, or the soldiers of a particular company or regiment. What is required here is a method of grading these individuals with reference to one another, by means of tests which need not necessarily have any relation to any external standard of mental perfection.

The process here is as if one were to be told to pick out of all the automobiles in a garage the best one, the next best, and so on, classifying these particular cars and no others with relation to one another and not with respect to any standards of automobile perfection introduced from outside. None of the cars might be perfect; perhaps the best one of the lot has leaky piston-rings and none of them will climb a 10 per cent. grade on high gear. It is a comparatively easy matter, however, to devise a few simple tests that will grade a dozen or fifty automobiles in regard to their relative ability to climb hills, carry loads, and perform the other services expected of an automobile. The one that will climb hills the best may not also be the one that will carry the heaviest load or travel the most miles on a gallon of gasolene, but out of such a series of group tests any one interested can readily determine which of all the automobiles in the group is the best general purpose car, which the poorest, and about where the others grade with reference to these two extremes.

That is about the process that a man engaged in the automobile trucking business would use in determining which one of the cars he has available is best adapted for a particular piece of hauling that is to be done. He wants to know which of his cars he can rely upon for any one of many different sorts of service, but he particularly wants to know all the time which of them are worth spending money on for repairs and improvements and general overhauling and which are either so poorly constructed in the first place or so hopelessly out of repair that it is cheaper to scrap them than to spend any more money on trying to make them fit for service.

In other words, the automobile owner needs to know which of his cars, however poor its present ability, has such inherent qualities as to justify the belief that it can be made more efficient by proper attention and reasonable expenditure of money.

Now, that is precisely what the employer of workers, the commander of soldiers, the teacher of a class or any one else charged with responsibility for the performance of any sort of tasks by any group of human beings, wants to know about the individuals under his direction. He should know or be able to determine readily not alone what each of the individuals can actually do and which ones can do particular tasks better than the others, but it is important for him to know the relative capacities of the entire group, so that he can determine, as in the case of the automobiles which have been used as an illustration, which of them are most worth spending time and effort upon in the expectation that they will learn to do even more difficult tasks, and which of them are so hopelessly incapable that nothing is to be expected of them except the simplest routine performances.

Now, the man who operates a fleet of automobile trucks does not stop when he has made a comparison of the vehicles in his garage with one another, but is constantly comparing the performance of each with standards established by other cars, machines of different makes, and with new machines. There exists, and he is constantly conscious of its existence, an ideal standard of performance for automobiles to which his cars must conform as nearly as possible if their service is to be satisfactory.

So, in measuring human capacity, it is not enough to compare the individuals of a group with one another, though this is essential and for some purposes temporarily sufficient; there are available standards based upon the actual achievements of individuals of known capacity by which the mental powers of any and all individuals may be gauged. It will readily be seen that the employer of a number of persons—engaged, let us say, in some specific mechanical or clerical operation—needs to know not only whether some of these are capable of being trained to do better work and some so incapable of further training that it would be cheaper to discharge them and fill their places with more intelligent persons, but also to know how any particular group of employees compares in average intelligence and how each one of the group compares in individual intelligence with the average or higher-than-average capacity of those outside of his own particular business establishment who are engaged in similar work.

This is a matter of dollars and cents to the employer. If he can obtain a standard that is universal or nearly so, that tells him, in fact, what all of the employers in his line of business have found to be the average or the limits of mental capacity possessed by workers of a particular class, then he is in a position to determine whether he is getting equally good service for the wages which he pays as is obtained by other employers requiring similar service.