The differences in memory which men exhibit are not, among their other
human qualities, the least. As is well known, this difference is
expressed not only in the vigor, reliability, and promptness of their
memory, but also in the field of memory, in the accompaniment of rapid
prehensivity by rapid forgetfulness, or slow prehensivity and slow
forgetfulness, or in the contrast between narrow, but intense memory,
and broad but approximate memory.
Certain special considerations arise with regard to the field of
greatest memory. As a rule, it may be presupposed that a memory which
has developed with especial vigor in one direction has generally done
this at the cost of memory in another direction. Thus, as a rule, memory
for numbers and memory for names exclude each other. My father had so
bad a memory for names that very frequently he could not quickly recall
my Christian name, and I was his own son. Frequently he had to repeat
the names of his four brothers until he hit upon mine, and that was not
always a successful way.[223] When he undertook an introduction it was
always: “My honored m--m--m,”--“The dear friend of my youth m--m--m.” On
the other hand, his memory for figures was astounding. He noted and
remembered not only figures that interested him for one reason or
another, but also those that had not the slightest connection with him,
and that he had read merely by accident. He could recall instantaneously
the population of countries and cities, and I remember that once, in the
course of an accidental conversation, he mentioned the production of
beetroot in a certain country for the last ten years, or the factory
number of my watch that he had given me fifteen years before and had
never since held in his hand. He often said that the figures he carried
in his head troubled him. In this regard the symptom may be mentioned
that he was not a good mathematician, but so exceptional a card player
that nobody wanted to play with him. He noticed every single card dealt
and could immediately calculate what cards each player had, and was able
to say at the beginning of the game how many points each must have.
Such various developments are numerous and of importance for us because
we frequently are unwilling to believe the witness testifying in a
certain field for the reason that his memory in another field had shown
itself to be unreliable. Schubert and Drobisch cite examples of this
sort of thing, but the observations of moderns, like Charcot and Binet,
concerning certain lightning calculators (Inaudi, Diamandi, etc.),
confirm the fact that the memory for figures is developed at the expense
of other matters. Linné tells that Lapps, who otherwise note nothing
whatever, are able to recognize individually each one of their
numberless reindeer. Again, the Dutch friend of flowers, Voorhelm, had a
memory only for tulips, but this was so great that he could recognize
twelve hundred species of tulips merely from the dry bulbs.
These fields seem to be of a remarkably narrow extent. Besides
specialists (numismatists, zoologists, botanists, heralds, etc.) who,
apart from their stupendous memory for their particular matters, appear
to have no memory for other things, there are people who can remember
only rhymes, melodies, shapes, forms, titles, modes, service,
relationships, etc. V. Volkmar has devoted some space to showing this.
He has also called attention to the fact that the semi-idiotic have an
astounding memory for certain things. This has been confirmed by other
students. One of them, Du Potet,[224] who is perhaps the expert in the
popular mind of the Austrian Alps, has made it especially clear. As in
all mountainous regions there are a great number of those unfortunate
idiots who, when fully developed, are called cretins, and in their
milder form are semi-human, but do not possess intelligence enough to
earn their own living. Nevertheless, many of them possess astounding
memories for certain things. One of them is thoroughly conversant with
the weather prophecy in the calendar for the past and the present year,
and can cite it for each day. Another knows the day and the history of
every saint of the Catholic church. Another knows the boundaries of
every estate, and the name, etc., of its owner. Another knows each
particular animal in a collective herd of cattle, knows to whom it
belongs, etc. Of course not one of these unfortunates can read. Drobisch
mentions an idiotic boy, not altogether able to speak, who, through the
untiring efforts of a lady, succeeded finally in learning to read. Then
after hasty reading of any piece of printed matter, he could reproduce
what he had read word for word, even when the book had been one in a
foreign and unknown tongue. Another author mentions a cretin who could
tell exactly the birthdays and death-days of the inhabitants of his town
for a decade.
It is a matter of experience that the semi-idiotic have an excellent
memory and can accurately reproduce events which are really impressive
or alarming, and which have left effects upon them. Many a thing which
normal people have barely noticed, or which they have set aside in their
memory and have forgotten, is remembered by the semi-idiotic and
reproduced. On the contrary, the latter do not remember things which
normal people do, and which in the latter frequently have a disturbing
influence on the important point they may be considering. Thus the
semi-idiotic may be able to describe important things better than normal
people. As a rule, however, they disintegrate what is to be remembered
too much, and offer too little to make any effective interpretation
possible. If such a person, e.g., is witness of a shooting, he notices
the shot only, and gives very brief attention to what precedes, what
follows, or what is otherwise contemporary. Until his examination he not
only knows nothing about it, but even doubts its occurrence. This is the
dangerous element in his testimony. Generally it is right to believe his
kind willingly. “Children and fools tell the truth,” what they say bears
the test, and so when they deny an event there is a tendency to overlook
the fact that they have forgotten a great deal and hence to believe that
the event had really not occurred.
Similar experiences are yielded in the case of the memory of children.
Children and animals live only in the present, because they have no
historically organic ideas in mind. They react directly upon stimuli,
without any disturbance of their idea of the past. This is valid,
however, only for very small children. At a later age children make good
witnesses, and a well-brought-up boy is the best witness in the world.
We have only to keep in mind that later events tend in the child’s mind
to wipe out earlier ones of the same kind.[225] It used to be said that
children and nations think only of the latest events. And that is
universally true. Just as children abandon even their most precious toys
for the sake of a new one, so they tell only the latest events in their
experience. And this is especially the case when there are a great many
facts--e.g., repeated mal-treatment or thefts, etc. Children will tell
only of the very last, the earlier one may absolutely have disappeared
from the memory.
Bolton,[226] who has made a systematic study of the memory of children,
comes to the familiar conclusion that the scope of memory is measured by
the child’s capacity of concentrating its attention. Memory and acute
intelligence are not always cognate (the latter proposition, true not
for children alone, was known to Aristotle). As a rule girls have better
memory than boys (it might also be said that their intelligence is
generally greater, so long as no continuous intellectual work, and
especially the creation of one’s own ideas, is required). Of figures
read only once, children will retain a maximum of six. (Adults, as a
rule, also retain no more.) The time of forgetting in general has been
excellently schematized by Ebbinghaus. He studied the forgetting of a
series of thirteen nonsense syllables, previously learned, in such a way
as to be able to measure the time necessary to re-learn what was
forgotten. At the end of an hour he needed half the original time, at
the end of eight hours two-thirds of that time. Then the process of loss
became slower. At the end of twenty-four hours he required a third, at
the end of six days a fourth, at the end of a month a clear fifth, of
the time required at first.
I have tested this in a rough way on various and numerous persons, and
invariably found the results to tally. Of course, the measure of time
alters with the memory in question, but the relations remain identical,
so that one may say approximately how much may be known of any subject
at the end of a fixed time, if only one ratio is tested. To criminalists
this investigation of Ebbinghaus’ is especially recommended.
The conditions of prehensivity of particular instances are too uncertain
and individual to permit any general identifications or
differentiations. There are certain approximating propositions--e.g.,
that it is easier to keep in mind rhymed verse than prose, and definite
rows and forms than block masses. But, on the one hand, what is here
involved is only the ease of memory, not the content of memory, and on
the other hand there are too many exceptions--e.g., there are many
people who retain prose better than verse. Hence, it is not worth while
to go further in the creation of such rules. Forty or fifty years ago,
investigations looking toward them had been pursued with pleasure, and
they are recorded in the journals of the time.
That aged persons have, as is well known, a good memory for what is long
past, and a poor one for recent occurrences is not remarkable. It is to
be explained by the fact that age seems to be accompanied with a
decrease of energy in the brain, so that it no longer assimilates
influences, and the imagination becomes dark and the judgment of facts
incorrect. Hence, the mistakes are those of apperception of new
things,--what has already been perceived is not influenced by this loss
of energy.
Again, it should not rouse astonishment that so remarkable and
delicately organized a function as memory should be subject to anomalies
and abnormalities of all kinds. We must take it as a rule not to assume
the impossibility of the extraordinary phenomena that appear and to
consult the expert about them.[227] The physician will explain the
pathological and pathoformic, but there is a series of memory-forms
which do not appear to be diseased, yet which are significantly rare and
hence appear improbable. Such forms will require the examination of an
experienced expert psychologist who, even when unable to explain the
particular case, will still be able to throw some light on it from the
literature of the subject. This literature is rich in examples of the
same thing; they have been eagerly collected and scientifically studied
in the earlier psychological investigations. Modern psychology,
unfortunately, does not study these problems, and in any event, its task
is so enormous that the practical problems of memory in the daily life
must be set aside for a later time. We have to cite only a few cases
handled in literature.
The best known is the story of an Irish servant girl, who, during fever,
recited Hebrew sentences which she had heard from a preacher when a
child. Another case tells of a very great fool who, during fever,
repeated prolonged conversations with his master, so that the latter
decided to make him his secretary. But when the servant got well he
became as foolish as ever. The criminalist who has the opportunity of
examining deeply wounded, feverish persons, makes similar, though not
such remarkable observations. These people give him the impression of
being quite intelligent persons who tell their stories accurately and
correctly. Later on, after they are cured, one gets a different opinion
of their intelligence. Still more frequently one observes that these
feverish, wounded victims know more, and know more correctly about the
crime than they are able to tell after they have recovered. What they
tell, moreover, is quite reliable, provided, of course, they are not
delirious or crazy.
The cases are innumerable in which people have lost their memory for a
short time, or for ever. I have already elsewhere mentioned an event
which happened to a friend of mine who received a sudden blow on the
head while in the mountains and completely lost all memory of what had
occurred a few minutes before the blow. After this citation I got a
number of letters from my colleagues who had dealt with similar cases. I
infer, therefore, that the instances in which people lose their memory
of what has occurred before the event by way of a blow on the head, are
numerous.[228]
Legally such cases are important because we would not believe statements
in that regard made by accused, inasmuch as there seems to be no reason
why the events _before_ the wound should disappear, just as if each
impression needed a fixative, like a charcoal drawing. But as this
phenomenon is described by the most reliable persons, who have no axe to
grind in the matter, we must believe it, other things being equal, even
when the defendant asserts it. That such cases are not isolated is shown
in the fact that people who have been stunned by lightning have later
forgotten everything that occurred shortly before the flash. The case is
similar in poisoning with carbonic-acid gas, with mushrooms, and in
strangulation. The latter cases are especially important, inasmuch as
the wounded person, frequently the only witness, has nothing to say
about the event.
I cannot omit recalling in this place a case I have already mentioned
elsewhere, that of Brunner. In 1893 in the town of Dietkirchen, in
Bavaria, the teacher Brunner’s two children were murdered, and his wife
and servant girl badly wounded. After some time the woman regained
consciousness, seemed to know what she was about, but could not tell the
investigating justice who had been sent on to take charge of the case,
anything whatever concerning the event, the criminal, etc. When he had
concluded his negative protocol she signed it, Martha Guttenberger,
instead of Martha Brunner. Fortunately the official noted this and
wanted to know what relation she had to the name Guttenberger. He was
told that a former lover of the servant girl, an evil-mouthed fellow,
was called by that name. He was traced to Munich and there arrested. He
immediately confessed to the crime. And when Mrs. Brunner became quite
well she recalled accurately that she had definitely recognized
Guttenberger as the murderer.[229]
The psychological process was clearly one in which the idea,
“Guttenberger is the criminal,” had sunk into the secondary sphere of
consciousness, the subconsciousness,--so that it was only clear to the
real consciousness that the name Guttenberger had something to do with
the crime. The woman in her weakened mental condition thought she had
already sufficiently indicated this fact, so that she overlooked the
name, and hence wrote it unconsciously. Only when the pressure on her
brain was reduced did the idea that Guttenberger was the murderer pass
from the subconscious to the conscious. Psychiatrists explain the case
as follows:
The thing here involved is retrograde amnesia. It is nowadays believed
that this phenomenon in the great majority of cases occurs according to
the rule which defines traumatic hysteria, i.e., as ideogen. The
ideational complexes in question are forced into the subconsciousness,
whence, on occasion, by aid of associative processes, hypnotic
concentration, and such other similar elements, they can be raised into
consciousness. In this case, the suppressed ideational complex
manifested itself in signing the name.
All legal medicine discusses the fact that wounds in the head make
people forget single words. Taine, Guerin, Abercrombie, etc., cite many
examples, and Winslow tells of a woman who, after considerable bleeding,
forgot all her French. The story is also told that Henry Holland had so
tired himself that he forgot German. When he grew stronger and recovered
he regained all he had forgotten.
_Now would we believe a prisoner who told us any one of these things?_
The phenomena of memories which occur in dying persons who have long
forgotten and never even thought of these memories, are very
significant. English psychologists cite the case of Dr. Rush, who had in
his Lutheran congregation Germans and Swedes, who prayed in their own
language shortly before death, although they had not used it for fifty
or sixty years. I can not prevent myself from thinking that many a
death-bed confession has something to do with this phenomenon.[230]
At the boundary between incorrect perception and forgetting are those
cases in which, under great excitement, important events do not reach
consciousness. I believe that the responsibility is here to be borne by
the memory rather than by sense-perception. There seems to be no reason
for failing to perceive with the senses under the greatest excitement,
but there is some clearness in the notion that great excitement causes
what has just been perceived to be almost immediately forgotten. In my
“Manual” I have discussed a series of cases of this sort, and show how
the memory might come into play. None of the witnesses, e.g., had seen
that Mary Stuart received, when being executed, two blows. In the case
of an execution of many years ago, not one of those present could tell
me the color of the gloves of the executioner, although everyone had
noticed the gloves. In a train wreck, a soldier asserted that he had
seen dozens of smashed corpses, although only one person was harmed. A
prison warden who was attacked by an escaping murderer, saw in the
latter’s hand a long knife, which turned out to be a herring. When
Carnot was murdered, neither one of the three who were in the carriage
with him, nor the two foot-men, saw the murderer’s knife or the delivery
of the blow, etc.
How often may we make mistakes because the witnesses--in their
excitement--have forgotten the most important things!