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introductory series. The task which I put before them in a number of
variations was this: I used lists of words of which half, or one more
or less than half, belonged to one single conceptional group. There
were names of flowers, or cities, or poets, or parts of the body, or
wild animals, and so on. The remaining words of the list, on the other
hand, were without inner connection and without similarity. The
similar and the dissimilar words were mixed. The subjects listened to
such a list of words and then had to decide without counting from the
mere impression whether the similar words were more or equally or less
numerous than the dissimilar words. In other experiments the
arrangement was that two different lists were read and that in the two
lists a larger or smaller number of words were repeated from the first
list. Here, too, the subjects had to decide from the mere impression
whether the repeated words were in the majority or not. In every
experiment the judgment referred to those words which belonged to the
same group and which were in this sense uniform, or to the repeated
words, and it had to be stated with reference to them whether their
number was larger, equal to, or smaller than the different words. If
all replies had been correct, the judgment would have been 40 per cent
equal, 30 per cent smaller, and 30 per cent larger, as they were
arranged in perfect symmetry. As soon as I had the results from the
students, we figured out for every one what number he judged equal,
smaller, or greater. Then we divided the equal judgments by 2 and
added half of them to the larger and half to the smaller judgments. In
this way we were enabled by one figure to characterize the whole
tendency of the individual. We found that in the whole student body
there was a tendency to underestimate the number of the similar or of
the repeated words. The majority of my students had a stronger
impression from the varying objects than from those which were in a
certain sense equal. Yet this tendency appeared in very different
degrees and for about a fourth of the participants the opposite
tendency prevailed. They received a stronger impression from the
uniform ideas.

I had coupled with these experimental tests a series of questions, and
had asked every subject to express with fullest possible self-analysis
his practical attitude to monotony in life. Every one had to give an
account whether in the small habits of life he liked variety or
uniform repetition. He was asked especially as to his preferences for
or against uniformity in the daily meals, daily walks, and so on.
Furthermore he had to report how far he is inclined to stick to one
kind of work or to alternate his work, how far he welcomes the idea
that vocational work may bring repetition, and so on. And finally I
tried to bring the results of these self-observations into relation
with the results of those experiments. It was here that the opposite
of the hypothesis which I had presupposed suggested itself to me with
surprising force. I found that just the ones who perceive the
repetition least hate it most, and that those who have a strong
perception of the uniform impressions and who overestimate their
number are the ones who on the whole welcome repetition in life.

As soon as I had reached this first experimental result, I began to
see how it might harmonize with known psychological facts. Some years
ago a Hungarian psychologist[37] showed by interesting experiments
that if a series of figures is exposed to the eye for a short fraction
of a second, equal digits are seen only once, and he came to the
conclusion that equal impressions in such a series inhibit each other.
In the Harvard laboratory we varied these experiments by eliminating
the spatial separation of those numbers. In our experiments the digits
did not stand side by side, but followed one another very quickly in
the same place.[38] Similar experiments we made with colors and so on.
Here, too, we found that quickly succeeding equal or very similar
impressions have a tendency to inhibit each other or to fuse with
each other. Where such an inhibition occurs, we probably ought to
suppose that the perception of the first impression exhausts the
psychical disposition for this particular mental experience. The
psychophysical apparatus becomes for a moment unable to arouse the
same impression once more.

The above described new experiments suggest to me that this inhibition
of equal or similar impressions is found unequally developed in
different individuals. They possess a different tendency to temporary
exhaustion of psychophysical dispositions. There are evidently persons
who after they have received an impression are unable immediately to
seize the same impression again. Their attention and their whole inner
attitude fails. But there are evidently other persons for whom, on the
contrary, the experience of an impression is a kind of inner
preparation for arousing the same or a similar impression. In their
case the psychophysical dispositions become stimulated and excited,
and therefore favor the repetition. If, as in our experiments, the
task is simply to judge the existence of equal or similar impressions
without any strain of attention, the one group of persons must
underestimate the number of the equal impressions because many words
are simply inhibited in their minds and remain neglected, the other
groups of persons must from their mental dispositions overestimate the
number of similar words. From here we have to take one step more. If
these two groups of persons have to perform a task in which it is
necessary that not a single member of a series of repetitions be
overlooked, it is clear that the two groups must react in a very
different way. Now a perfect perception of every single member is
forced on them. Those who grasp equal impressions easily, and who are
prepared beforehand for every new repetition by their inner
dispositions, will follow the series without strain and will
experience the repetition itself with true satisfaction. On the other
hand, those in whom every impression inhibits the readiness to receive
a repetition, and whose inner energy for the same experience is
exhausted, must feel it as a painful and fatiguing effort if they are
obliged to turn their attention to one member after another in a
uniform series. This mental torture is evidently the displeasure which
such individuals call the dislike of monotony in their work. Whether
this theoretical view is correct, we have to determine by future
studies. In our Harvard laboratory we have now proceeded from such
preparatory mass experiments to subtle investigations on a small
number of persons well trained in psychological self-observation with
whom the conditions of the experiment can be varied in many
directions.[39]

It would seem probable that such experiments might also win
psychotechnical significance. A short series of tests which would have
to be adapted to the special situations, and which for the simple
wage-earner would have to be much easier than those sketched above,
would allow it to be determined beforehand whether an individual will
suffer from repetition in work. Even if we abstract from arguments of
social reform and consider exclusively the economic significance, it
must seem important that labor which involves much repetition be
performed by men and women whose mental dispositions favor an easy
grasp of successive uniform impressions. Experimentation could secure
the selection of the fit workmen and the complaint of monotony would
disappear. The same selection could be useful in the opposite
direction, as many economic occupations, especially in our time of
automatic machines, demand a quick and often rhythmical transition
from one activity to another. It is evident that those whose natural
dispositions make every mental excitement a preparation not for the
identical but for the contrasting stimulation will be naturally
equipped for this kind of economic tasks.




XVII

ATTENTION AND FATIGUE


The problem of monotony may lead us on to other conditions through
which attention is hindered and the product of labor thereby
decreased. The psychologist naturally first thinks of external
distractions of attention. If he turns to practical studies of the
actual economic life, he is often decidedly surprised to find how
little regard is given to this psychophysical factor. In industrial
establishments in which the smallest disturbance in the machine is at
once remedied by a mechanic in order that the greatest possible
economic effect may be secured, frequently nobody takes any interest
in the most destructive disturbances which unnecessarily occur in the
subtlest part of the factory mechanism, namely, the attention
apparatus of the laborers. Such an interference with attention must,
for instance, be recognized when the workingman, instead of devoting
himself to one complex function, has to carry out secondary movements
which appear to be quite easily performed and not to hinder him in his
chief task. Often his own feeling may endorse this impression. Of
course the individual differences in this direction are very great.
The faculty of carrying on at the same time various independent
functions is unequally distributed and the experiment can show this
clearly. It is also well known from practical life that some men can
easily go on dictating to a stenographer while they are affixing their
signature to several hundred circular letters, or can continue their
fluent lecture while they are performing experimental demonstrations.
With others such a side activity continually interrupts the chief
function. Then some succeed better than others in securing a certain
automatism of the accessory function to such a point that its special
acts do not come to consciousness at all. For example, I watched a
laborer who was constantly engaged in a complicated technical
performance, and he seemed to give to it his full attention.
Nevertheless he succeeded in moving a lever on an automatic machine
which stood near by whenever a certain wheel had made fifty
revolutions. During all his work he kept counting the revolutions
without being conscious of any idea of number. A system of motor
reactions had become organized which remained below the threshold of
consciousness and which produced only at the fiftieth recurrence the
conscious psychical impulse to perform the lever movement. Yet whether
the talent for such simultaneous mastery of independent functions be
greater or smaller and the demand more or less complex, in every case
the principal action must be hampered by the side issue. To be sure,
it may sometimes be economically more profitable to allow the
hindrance to the chief work in order to save the expense of an extra
man to do the side work. In most cases, however, such a consideration
is not involved; it is simply an ignoring of the psychological
situation. As the accessory work seems easy, its hindering influence
on other functions is practically overlooked. Psychological laboratory
experiments have shown in many different directions that simultaneous
independent activities always disturb and inhibit one another.

We must not forget that even the conversations of the laborers belong
in this psychophysical class. Where a continuous strain of attention
has produced a state of fatigue, a short conversation will bring a
certain relief and relaxation, and the words which the speaker hears
in reply will produce a general stimulation of psychical energy for
the moment. Moreover, the mere existence of the social conversational
intercourse will raise the general emotional mood, and this feeling of
social pleasure may be the source from which may spring new
psychophysical powers. Nevertheless the fundamental fact, after all,
is that any talking during the labor, so far as it is not necessary
for the work itself, surely involves a distraction of attention. Here,
too, the individual is not conscious of the effect. He feels certain
that he can perform his task just as well, and even the piece-worker,
who is anxious to earn as much as possible, is convinced that he does
not retard himself by conversation. But the experiments which have
been carried on in establishments with scientific management speak
decidedly against such a supposition. A tyrannical demand for silence
would, of course, be felt as cruelty, and no suggestion of a jail-like
discipline would be wise in the case of industrial labor, for evident
psychological reasons. But various factories in rearranging their
establishments according to the principles of scientific management
have changed the positions of the workmen so that conversations become
more difficult or impossible. The result reported seems to be
everywhere a significant increase of production. The individual
concentrates his mind on the task with an intensity which seems beyond
his reach as long as the inner attitude is adjusted to social contact.
The help which is rendered by the feeling of social coöperation, on
the other hand, is not removed by the mere abstaining from speaking.
Interesting psychopedagogical experiments have, indeed, demonstrated
that working in a common room produces better results than isolated
activity. This is not true of the most brilliant, somewhat nervous
school children, who achieve in their own room at home more than in
the classroom. But for the average, which almost alone is in question
for life in the factory, the consciousness of common effort is a
source of psychophysical reinforcement. This evidently remains
effective when the workingmen can see one another, even if the
arrangement of the seats precludes the possibility of chatting during
the work.

However, by far the more important cause of distraction of attention
lies in those disturbances which come from without. Here again the
chief interest ought to be attached to those interferences which the
workman himself no longer feels as such. In a great printing-shop a
woman who was occupied with work which demanded her fullest attention
was seated at her task in an aisle where trucking was done. Removing
this operator to a quiet corner caused an increase of 25 per cent in
her work.[40] To be sure there are many such disturbances in factory
life which can hardly be eliminated with the technical means of
to-day. For instance, the noise of the machines, which in many
factories makes it impossible to communicate except by shouting, must
be classed among the real psychological interferences in spite of the
fact that the laborers themselves usually feel convinced that they no
longer notice it at all. Still more disturbing are strong rhythmical
sounds, such as heavy hammer blows which dominate the continuous
noises, as they force on every individual consciousness a
psychophysical rhythm of reaction which may stand in strong contrast
to that of a man's own work. From the incessant inner struggle of the
two rhythms, the one suggested by the labor, the other by the external
intrusion, quick exhaustion becomes unavoidable.

If it were our purpose to elaborate a real system of psychological
economics, we should have to proceed here to a careful study of the
influences of fatigue on the industrial achievement. We should have to
discuss the various kinds of fatigue and exhaustion, the conditions of
restoration, and the whole group of related problems of psychophysics.
But this is the one field which has been thoroughly ploughed over by
science and by practical life in the course of the last decades. No
new suggestion and no new hint of the importance of the problem is
needed here. Our short discussion was planned to be confined to those
regions which have not been worked up in systematic investigations
and for which new devices seemed desirable. Hence we do not reproduce
here the rich material of facts which the physiologists and
psychophysicists have brought together in the last half-century, the
importance of which for industrial labor is perfectly evident.
Moreover, the practical applications and the insight into the social
needs have transformed the factories themselves into one big
laboratory in which the problem of fatigue has been studied by
practical experiments. The problem of the dependence of fatigue and
output upon the length of the working day has been tested in
numberless places with the methods of really exact research, as it was
easy to find out how the achievement of the laborers became
quantitatively and qualitatively changed by the shortening of the
working hours.

When in one civilized country after another the exhaustingly long
working days of the industrial wage-earner were shortened more and
more, the theoretical discussions of the legislators and of the social
reformers were soon supplemented by careful statistical inquiries in
the factories. It was found that everywhere, even abstracting from all
other cultural and social interests, a moderate shortening of the
working day did not involve loss, but brought a direct gain. The
German pioneer in the movement for the shortening of the workingman's
day, Ernst Abbé, the head of one of the greatest German factories,
wrote many years ago that the shortening from nine to eight hours,
that is, a cutting-down of more than 10 per cent, did not involve a
reduction of the day's product, but an increase, and that this
increase did not result from any supplementary efforts by which the
intensity of the work would be reinforced in an unhygienic way.[41]
This conviction of Abbé still seems to hold true after millions of
experiments over the whole globe. But the problem of fatigue has
forced itself on the consideration of the men of affairs from still
another side. It has been well known for a long while how intimate the
relations are between fatigue and industrial accidents. The statistics
of the various countries and of the various industries do not
harmonize exactly, but a close connection between the number of
accidents and the hours of the day can be recognized everywhere.
Usually the greatest number of injuries occurs between ten and eleven
o'clock in the forenoon and between three and four o'clock in the
afternoon. The different distribution of the working hours, and of the
pauses for the meals, make the various statistical tables somewhat
incomparable. But it can be traced everywhere that in the first
working hours in which fatigue does not play any considerable rôle,
the number of accidents is small, and that this number sinks again
after the long pauses. It is true that the number also becomes
somewhat smaller at the end of the forenoon and of the afternoon
period, but this seems to have its cause in the fact that with growing
fatigue and with the feeling that the end of the working period is
near, the rhythm of the activity becomes much slower, and with such
slower movements the danger of accidents is greatly reduced. In a
similar way the factories have had to give the fullest attention to
the fatigue problem in its relation to the distribution of pauses, and
above all in its relation to the advisable speed of the machines, the
limits of which are set by the fatigue of the workingmen, and still
more of the working-women.

The legislatures, the labor unions, and the manufacturers have then
had this problem of fatigue constantly before their eyes.[42] On the
other hand, the psychologists and physiologists have continuously
studied the fatigue and restoration of the muscle system and of the
central nervous system, and have analyzed the facts with the subtlest
methods. Yet, in spite of this, it cannot be denied that a real mutual
enrichment has so far hardly been in question. On the contrary, the
whole situation has again demonstrated the old experience. The mere
trying and trying again in practical life can never reach the maximum
effects which may be secured by systematic, scientifically conducted
efforts. On the other side the studies of the theoretical scholars can
never yield the highest values for civilization if the problems which
offer themselves in practical life are ignored. The theorists have to
prepare the ground, and in this preparatory work they must, indeed,
remain utterly regardless of any practical situations. But after that
a second stage must be reached at which on the foundation of this
neutral research special theoretical investigations are undertaken
which originate from practical conditions. As long as industrial
managers have no contact with the experiments of the laboratory and
the experimentalists are shy of any contact with the industrial
reality, humanity will pass through social suffering. The hope of
mankind will be realized by the mutual fertilization of knowing and
doing.

The practical efforts of the factories have, indeed, not yet reached
the point at which the greatest possible achievement which can be
reached without over-fatigue may be secured. We called the
abbreviation of the working day an experimental scheme. The question
of reducing the working hours is so simple that no further special
experiments are needed. But when we come to the questions of the
pauses at work, the speed of work and similar factors related to
fatigue, the situation is by far more complicated, and the often
capricious changes in the plant have very little in common with a
systematic experiment. Some well-known studies of the efficiency
engineers clearly demonstrate the possibility of such systematic
efforts. The best-known case is probably Taylor's study of the
pig-iron handlers of the Bethlehem Steel Company. He found that the
gang of 75 men was loading on the average about 12-1/2 tons per man
per day. When he discussed with various managers the question of what
output would be the possible maximum, they agreed that under premium
work, piecework, or any of the ordinary plans for stimulating the men,
an output of 18 to 25 tons would be the extreme possibility. Then he
proceeded to a systematic study of the fatigue in its relation to the
burden and of the best possible relation between working time and
resting time. His first efforts to find formulas were unsuccessful,
because he calculated only the actual mechanical energy exerted and
found that some men were tired after exerting energy of 1/8 hp., while
others seemed to be able to produce the energy of 1/2 hp. without
greater fatigue. But soon he discovered the mistake in his figures.
He had considered only the actual movements, and had neglected the
period in which the laborer was not moving and was not exerting
energy, but in which a weight was pulling his arms and demanding a
corresponding muscular effort. As soon as this muscular achievement
was taken into account, too, he found that for each particular weight
a definite relation exists between the time that a man is under a
heavy load and the time of rest. For the usual loads of 90 pounds, he
found that a first-class laborer must not work more than 43 per cent
of time working day and must be entirely without load 57 per cent. If
the load becomes lighter, the relation is changed. If the workman is
handling a half pig weighing 46 pounds, he can be under load 58 per
cent of the day and only has to rest during 42 per cent.[43]

As soon as these figures were experimentally secured, Taylor selected
fit men, and did not allow them to lift and to carry the loads as they
pleased, but every movement was exactly prescribed by foremen who
timed exactly the periods of work and rest. If he had simply promised
his men a high premium in case they should carry more than the usual
12 tons a day, they would have burdened themselves as heavily as
possible and would have carried the load as quickly as possible, thus
completely exhausting themselves after three or four hours of labor.
In spite of such senseless exaggeration of effort in the first hours,
the total output for the day would have been relatively small. Now the
foremen determined exactly when every individual should lift and move
the load and when he should sit quietly. The result was that the men,
without greater fatigue, were able to carry 47-1/2 tons a day instead
of the 12-1/2 tons. Their wages were increased 60 per cent. Such a
trivial illustration demonstrates very clearly the extreme difference
between an increase of the economic achievement by scientific,
experimental investigation and a mere enforcing of more work by
artificially whipping-up the mind with promises of extraordinary
wages. Yet even such rules as the scientific management engineers have
formed, may be elaborated to more lasting prescriptions as soon as the
purely psychological factors are brought more into the foreground and


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