Hugo Münsterberg, answered from the texts and cited to the page.
The question goes to the heart of what I set out to demonstrate with the psychotechnic method. Personalities entering the world of affairs present an unlimited manifoldness of talents, abilities, and functions of the mind — variations of will and feeling, of perception and thought, of attention and emotion, of memory and imagination — and from this manifoldness it necessarily follows that some are more, some less, fit for any particular economic task.1
Aptitude testing is the systematic means of discovering which. The difficulty is that people do not know themselves. Boys and girls grow up without recognizing their psychical weaknesses, and the exceptional strength of one or another mental function goes equally unnoticed. A man may have an unusually developed memory of the visual type while his neighbor's memory is wholly acoustical, and neither has the slightest idea that their contents of consciousness are fundamentally different from each other.2
What the individual's own self-observation cannot reveal, the laboratory can measure. The method takes two forms, depending on the nature of the work. Where the vocation demands several relatively independent mental functions — attention, memory, speed of association, intelligence — each is examined separately by its own experimental procedure.3
Where success depends on the special cooperation of all factors at once, the situation as a whole is artificially reproduced on a reduced scale, so that exactly those mental energies are aroused which the work itself demands.4 My experiments with motormen on the street railways illustrate the second approach: an apparatus in which figures passed across a screen at varying distances from a central line representing the track, requiring the subject to combine continuous attention with quick reaction and anticipatory imagination — precisely the mental combination whose absence leads to the death of hundreds every year.5
The practical gain is not trivial. A man with the focusing type of attention will fail at mill work requiring expanded watchfulness over many moving shuttles, yet surpass his competitors in the next mill where concentrated attention on a single point is demanded.6 Under present methods — that is, without psychological guidance — he would seek the wrong place, feel sure that industry and good will were sufficient, and meet only disappointment and drift.
The laboratory would have turned him in the right direction.7 That is what aptitude testing is: not a judgment on a man's worth, but the fitting of a particular mind to the work it can actually do well.
We simply start from the clear fact that the personalities which enter into the world of affairs present an unlimited manifoldness of talents and abilities and functions of the mind. From this manifoldness, it necessarily follows that some are more, some less, fit for the particular economic task.Psychology and Industrial Efficiency
Men with a pronounced visual type of memory and men with a marked acoustical type may live together without the slightest idea that their contents of consciousness are fundamentally different from each other.Psychology and Industrial Efficiency
The fluctuations of attention were tested by a long-continued crossing out of a letter in printed text; the intelligence by testing the memory for logical associations; the rapidity of mind by measuring the association times, and so on. In this case everything depended upon the resolution of the complex function into its elements.Psychology General and Applied
Either the complex function is divided into its parts, whenever these parts are relatively independent in the active performance, or the situation as a whole is artificially copied on a reduced scale, whenever the success depends upon the special cooperation of all factors.Psychology General and Applied
It is the lack of this power which leads to the death of hundreds and to the injury of thousands every year. It is of decisive importance to recognize the presence of this mental ability before a man is accepted for such service.Psychology General and Applied
The most industrious workman will be unsuccessful at such work if his attention is of the type that prevents him from such expansion of mental watchfulness. The same man might be most excellent as a worker in the next mill, where the work demanded was dependent upon strong concentration of attention on one point.American Problems
The man with the focusing attention might seek work in the mill where distributed attention is needed, and would feel sure that his industry and good will were sufficient to make him successful in his work. And yet the result would be disappointment and failure. Discouragement would ensue. He would soon lose his place, and drift on. The psychologist might have turned him in the right direction.American Problems