Criminal Psychology: A Manual for Judges, Practitioners,...

In many cases it is possible to control the imagination, but only when it is known that the images can not be as they are seen. Everybody is aware how a half-covered object at a distance, or objects accidentally grouped in one way or another, are taken for God knows what. Thus once, looking from my desk to my smoking table, I saw an enormous pair of tailor’s scissors half-covered by a letter. It remained identical under a number of repeated glances. Only when I thought vigorously that such a thing could not possibly be in my room did it disappear. A few scales of ashes, the lower round of the match safe, the metal trimmings of two cigar boxes half-covered by a letter and reflected by the uncertain light breaking through the branches of a tree, were all that the tailor’s scissors was composed of. If there had been such a thing in the house, or if I had believed something like it to exist in the house, I should have sought no further and should have taken my oath that I had seen the thing. It is significant that from the moment I understood the phenomenon I could not restore the image of the scissors. How often may similar things be of importance in criminal trials!

The so-called captivation of our visual capacity plays a not unimportant part in distinguishing correct from illusory seeing. In order to see correctly we must look straight and fully at the object. Looking askance gives only an approximate image, and permits the imagination free play. Anybody lost in a brown study who pictures some point in the room across the way with his eyes can easily mistake a fly, which he sees confusedly askance, for a great big bird. Again, the type of a book seems definitely smaller if the eyes are fixed on the point of a lead pencil with a certain distance before or above the book. And yet again, if you stand so that at an angle of about 90 degrees from the fixation point, you look at a white door in a dark wall, observing its extent in indirect vision, you will find it much higher than in direct vision.

These examples indicate how indirect vision may be corrected by later correct vision, but such correction occurs rarely. We see something indirectly; we find it uninteresting, and do not look at it directly. When it becomes of importance later on, perhaps enters into a criminal case, we think that we have seen the thing as it is, and often swear that “a fly is a big bird.”

There are a number of accidents which tend to complete illusion. Suppose that the vision of a fly, which has been seen indirectly and taken for a big bird happens to be synchronous with the shriek of some bird of prey. I combine the two and am convinced that I have seen that bird of prey. This may increase, so much so that we may have series of sense-illusions. I cite the example of the decorative theatrical artist, who can make the most beautiful images with a few, but very characteristic blots. He does it by emphasising what seems to us characteristic, e.g., of a rose arbor, in such a way that at the distance and under the conditions of illumination of the theatre we imagine we really see a pretty rose arbor. If the scene painter could give definite rules he would help us lawyers a great deal. But he has none, he proceeds according to experience, and is unable to correct whatever mistakes he has committed. If the rose arbor fails to make the right impression, he does not try to improve it—he makes a new one. This may lead to the conclusion that not all people require the same characteristics in order to identify a thing as such, so that if we could set the rose arbor on the stage by itself, only a part of the public would recognize it as properly drawn, the other part would probably not recognize it at all. But if, of an evening, there is a large number of decorations on the stage, the collective public will find the arbor to be very pretty. That will be because the human senses, under certain circumstances, are susceptible to sympathetic induction.

In the case of the rose arbor we may assume that the artist has typically represented the necessary characteristics of the arbor for one part of the audience, for another part those of a castle, for another part those of a forest, and for a fourth those of a background. But once an individual finds a single object to be correct, his senses are already sympathetically inductive, i.e., captivated for the correctness of the whole collection, so that the correctness passes from one object to the total number. Now, this psychic process is most clear in those optical illusions which recently have been much on public exhibition (the Battle of Gravelotte, the Journey of the Austrian Crown Prince in Egypt, etc.). The chief trick of these representations is the presenting of real objects, like stones, wheels, etc., in the foreground in such a way that they fuse unnoticeably with the painted picture. The sense of the spectator rests on the plastic objects, is convinced of their materiality and transfers the idea of this plasticity to the merely pictured. Thus the whole image appears as tri-dimensional.

The decorations of great parks at the beginning of the last century indicate that illumination and excited imagination are not alone in causing such illusions. Weber tells ecstatically of an alley in Schwetzing at the end of which there was a highly illuminated concave wall, painted with a landscape of mountains and water-falls. Everybody took the deception for a reality because the eye was captivated and properly inducted. The artist’s procedure must have been psychologically correct and must have counted upon the weakness of our observation and intellection. Exner points to the simple circumstance that we do not want to see that things under certain conditions must terminate. If we draw a straight line and cover an end with a piece of paper, every one wonders that the line is not longer when the paper is removed.

I know of no case in criminal procedure where illusions of this kind might be of importance, but it is conceivable that such illusions enter in numberless instances. This is especially susceptible of observation when we first see some region or object hastily and then observe it more accurately. We are astonished how fundamentally false our first conception was. Part of this falseness may be adduced to faults of memory, but these play little or no part if the time is short and if we are able to recall that the false conception appeared just as soon as we observed the situation in question. The essential reason for false conception is to be found only in the fact that our first hasty view was incorrectly inducted, and hence, led to illusions like those of the theatre. Thus, it is possible to take a board fence covered at points with green moss, for a moss-covered rock, and then to be led by this to see a steep cliff. Certain shadows may so magnify the size of the small window of an inn that we may take it to be as large as that of a sitting room. And if we have seen just one window we think all are of the same form and are convinced that the inn is a mansion. Or again, we see, half-covered, through the woods, a distant pool, and in memory we then see the possibly, but not necessarily, present river. Or perhaps we see a church spire, and possibly near it the roof of a house rises above the trees; then we are inducted into having seen a village, although there really are visible only the church and the house.

These illusions again, I must repeat, are of no importance if they are at all doubted, for then the truth is ascertained. When, however, they are not doubted and are sworn to, they cause the greatest confusion in trials. A bar-room quarrel, a swung cane, and a red handkerchief on the head, are enough to make people testify to having seen a great brawl with bloody heads. A gnawing rat, a window accidentally left open through the night, and some misplaced, not instantaneously discovered object, are the ingredients of a burglary. A man who sees a rather quick train, hears a shrill blowing of the whistle, and sees a great cloud, may think himself the witness of a wreck. All these phenomena, moreover, reveal us things as we have been in the habit of seeing them. I repeat, here also, that the photographic apparatus, in so far as it does not possess a refracting lens, shows things much more truly than our eye, which is always corrected by our memory. If I permit a man sitting on a chair to be photographed, front view, with his legs crossed and stretched far out, the result is a ludicrous picture because the boots seem immensely larger than the head of the subject. But the photograph is not at fault, for if the subject is kept in the same position and then the apparent size of head and boot are measured, we get accurately the same relation as on the photograph. We know by experience how big a head is. And hence, we ordinarily see all relations of size in proper proportion.

If, in a criminal case, we are dealing with a description of size, and it is given as it is known from experience, not as it really appears, then if experience has deceived us, our testimony is also wrong, although we pretend to have testified on the basis of direct sense-perception.

The matter of after-images, probably because of their short duration, is of no criminalistic importance. I did once believe that they might be of considerable influence on the perception of witnesses, but I have not succeeded in discovering a single example in which this influence is perceptible.

On the other hand, the phenomenon of irradiation, the appearance of dark bodies as covered with rays of light by adjacent luminosities, is of importance. This phenomenon is well-known, as are Helmholtz’s and Plateau’s explanations of it. But it is not sufficiently applied. One needs only to set a white square upon the blackest possible ground and at the same time a similar black square of equal size on a white ground, and then to place them under a high light, to perceive how much larger the white square appears to be. That such phenomena often occur in nature need not be expounded. Whenever we are dealing with questions of size it is indubitably necessary to consider the color of the object and its environment with respect to its background and to the resulting irradiation.