The only help against this is in the study by the presiding justice, not as lawyer but as psychologist, of the faces of the jury while the contending lawyers make their addresses. He must observe very narrowly and carefully every influence exercised by the speeches, which is irrelevant to the real problem, and then in summing up call it to the attention of the jury and bring them back to the proper point of view. The ability to do this is very marvelous, but it again is an exceedingly difficult performance.
Nowadays persuadability is hardly more studied but anybody who has empirically attained some proficiency in it has acquired the same tricks that are taught by theory. But these must be known if they are to be met effectively. Hence the study of the proper authors can not be too much recommended. Without considering the great authors of the classical period, especially Aristotle and Cicero, there are many modern ones who might be named.
Section 31. (i) Inference and Judgment.
The judgment to be discussed in the following section is not the judgment of the court but the more general judgment which occurs in any perception. If we pursue our tasks earnestly we draw from the simplest cases innumerable inferences and we receive as many inferences from those we examine. The correctness of our work depends upon the truth of both. I have already indicated how very much of the daily life passes as simple and invincible sense-perception even into the determination of a sentence, although it is often no more than a very complicated series of inferences each of which may involve a mistake even if the perception itself has been correct. The frequency with which an inference is made from sense- perception is the more astonishing inasmuch as it exceeds all that the general and otherwise valid law of laziness permits. In fact, it contradicts that law, though perhaps it may not do so, for a hasty inference from insufficient premises may be much more comfortable than more careful observation and study. Such hasty inference is made even with regard to the most insignificant things. In the course of an investigation we discover that we have been dealing only with inferences and that our work therefore has been for nothing. Then again, we miss that fact, and our results are false and their falsehood is rarely sought in these petty mistakes. So the witness may have "seen'' a watch in such and such a place when in reality he has only heard a noise that he took for the ticking of a watch and hence *inferred that there had really been a watch, that he had seen it, and finally *believed that he had seen it. Another witness asserts that X has many chickens; as a matter of fact he has heard two chickens cluck and infers a large number. Still another has seen footprints of cattle and speaks of a herd, or he knows the exact time of a murder because at a given time he heard somebody sigh, etc. There would be little difficulty if people told us how they had inferred, for then a test by means of careful questions would be easy enough—but they do not tell, and when we examine ourselves we discover that we do exactly the same thing and often believe and assert that we have seen or heard or smelt or felt although we have only inferred these things. Here belong all cases of correct or partly correct inference and of false inference from false sense perception. I recall the oft-cited story in which a whole judicial commission smelt a disgusting odor while a coffin was being exhumed only to discover that it was empty. If the coffin, for one reason or another, had not been opened all those present would have taken oath that they had an indubitable perception although the latter was only inferred from its precedent condition.
 Cf. H. Gross, Korrigierte Vorstellungen, in the Archiv, X, 109.
Exner cites the excellent example in which a mother becomes frightened while her child cries, not because the cry as such sounds so terrible as because of its combination with the consciousness that it comes from her own child and that something might have happened to it. It is asserted, and I think rightly, that verbal associations have a considerable share in such cases. As Stricker expresses it, the form of any conceptual complex whatever, brings out its appropriate word. If we see the *thing watch, we get the *word watch. If we see a man with a definite symptom of consumption the word tuberculosis occurs at once. The last example is rather more significant because when the whole complex appears mistakes are more remote than when merely one or another "safe'' symptom permits the appearance of the word in question. What is safe to one mind need not be so to another, and the notion as to the certainty of any symptom changes with time and place and person. Mistakes are especially possible when people are so certain of their "safe'' symptoms that they do not examine how they inferred from them. This inference, however, is directly related to the appearance of the word. Return to the example mentioned above, and suppose that A has discovered a "safe'' symptom of consumption in B and the word tuberculosis occurs to him. But the occurrence does not leave him with the word merely, there is a direct inference "B has tuberculosis.'' We never begin anything with the word alone, we attach it immediately to some fact and in the present case it has become, as usual, a judgment. The thought-movement of him who has heard this judgment, however, turns backward and he supposes that the judge has had a long series of sense-perceptions from which he has derived his inference. And in fact he has had only one perception, the reliability of which is often questionable.
 S. Exner: Entwurf zu einer physiologisehen Erklrung der psychischen Erscheinungen. Leipzig 1894.
 Studien ber die Assoziation der Vorstellungen. Vienna 1883.
Then there is the additional difficulty that in every inference there are leaps made by each inferer according to his character and training. And the maker does not consider whether the other fellow can make similar leaps or whether his route is different. E. g., when an English philosopher says, "We really ought not to expect that the manufacture of woolens shall be perfected by a nation which knows no astronomy,''—we are likely to say that the sentence is silly; another might say that it is paradoxical and a third that it is quite correct, for what is missing is merely the proposition that the grade of culture made possible by astronomy is such as to require textile proficiency also. "In conversation the simplest case of skipping is where the conclusion is drawn directly from the minor premise. But many other inferences are omitted, as in the case of real thinking. In giving information there is review of the thinking of other people; women and untrained people do not do this, and hence the disconnectedness of their conversation.'' In this fact is the danger in examining witnesses, inasmuch as we involuntarily interpolate the missing details in the skipping inferences, but do it according to our own knowledge of the facts. Hence, a test of the correctness of the other man's inference becomes either quite impossible or is developed coarsely. In the careful observation of leaping inferences made by witnesses—and not merely by women and the uneducated—it will be seen that the inference one might oneself make might either have been different or have proceeded in a different way. If, then, all the premises are tested a different result from that of the witness is obtained. It is well known how identical premises permit of different conclusions by different people.
 von Hartmann: Philosophie des Unbewussten. Berlin 1869.
In such inferences certain remarkable things occur which, as a rule, have a given relation to the occupation of the witness. So, e. g., people inclined to mathematics make the greatest leaps, and though these may be comparatively and frequently correct, the danger of mistake is not insignificant when the mathematician deals in his mathematical fashion with unmathematical things.
Another danger lies in the testimony of witnesses who have a certain sense of form in representation and whose inferential leaps consists in their omitting the detailed expression and in inserting the notion of form instead. I learned of this notable psychosis from a bookkeeper of a large factory, who had to provide for the test of numberless additions. It was his notion that if we were to add two and three are five, and six are eleven, and seven are eighteen we should never finish adding, and since the avoidance of mistakes requires such adding we must so contrive that the image of two and three shall immediately call forth the image of five. Now this mental image of five is added with the actual six and gives eleven, etc. According to this we do not add, we see only a series of images, and so rapidly that we can follow with a pencil but slowly. And the images are so certain that mistake is impossible. "You know how 9 looks? Well, just as certainly we know what the image of 27 and 4 is like; the image of 31 occurs without change.''
This, as it happens, is a procedure possible only to a limited type, but this type occurs not only among bookkeepers. When any one of such persons unites two events he does not consider what may result from such a union; he sees, if I may say so, only a resulting image. This image, however, is not so indubitably certain as in the case of numbers; and it may take all kinds of forms, the correctness of which is not altogether probable. E. g., the witness sees two forms in the dark and the flash of a knife and hears a cry. If he belongs to the type under discussion he does not consider that he might have been so frightened by the flashing knife as to have cried out, or that he had himself proceeded to attack with a stick and that the other fellow did the yelling, or that a stab or cut had preceded the cry—no, he saw the image of the two forms and the knife and he heard the cry and these leap together into an image. i. e., one of the forms has a cut above his brow. And these leaps occur so swiftly and with such assurance that the witness in question often believes himself to have seen what he infers and swears to it.
There are a great many similar processes at the bottom of impressions that depend only upon swift and unconscious inference. Suppose, e. g., that I am shown the photograph of a small section of a garden, through which a team is passing. Although I observe the image of only a small portion of the garden and therefore have no notion of its extent, still, in speaking of it, I shall proba- bly speak of a very big garden. I have inferred swiftly and unconsciously that in the fact that a wagon and horses were present in the pictured portion of the garden, is implied great width of road, for even gardens of average size do not have such wide roads as to admit wagons; the latter occurring only in parks and great gardens. Hence my conclusion: the garden must be very big. Such inferences are frequent, whence the question as to the source and the probability of the witness's information, whether it is positive or only an impression. Evidently such an impression may be correct. It will be correct often, inasmuch as impressions occur only when inferences have been made and tested repeatedly. But it is necessary in any case to review the sequence of inferences which led to this impression and to examine their correctness. Unfortunately the witness is rarely aware whether he has perceived or merely inferred.
 Cf. Gross's Archiv, I, 93, II, 140, III, 250, VII, 155.
Examination is especially important when the impression has been made after the observation of a few marks or only a single one and not very essential one at that. In the example of the team the impression may have been attained by inference, but frequently it will have been attained through some unessential, purely personal, determinative characteristic. "Just as the ancient guest recognizes his friend by fitting halves of the ring, so we recognize the object and its constitution from one single characteristic, and hence the whole vision of it is vivified by that characteristic.''
 H. Aubert: Physiologie der Netzhaut. Breslau 1865.
All this is very well if no mistakes are made. When Tertullian said, "Credo quia impossibile est,'' we will allow honesty of statement to this great scholar, especially as he was speaking about matters of religion, but when Socrates said of the works of Heraclitus the Obscure: "What I understand of it is good; I think that what I do not understand is also good''—he was not in earnest. Now the case of many people who are not as wise as Tertullian and Socrates is identical with theirs. Numerous examinations of witnesses made me think of Tertullian's maxim, for the testimonies presented the most improbable things as facts. And when they even explained the most unintelligible things I thought: "And what you do not understand is also good.''
This belief of uncultured people in their own intelligence has been most excellently portrayed by Wieland in his immortal "Abderites.'' The fourth philosopher says: "What you call the world is essentially an infinite series of worlds which envelop one another like the skin of an onion.'' "Very clear,'' said the Abderites, and thought they understood the philosopher because they knew perfectly well what an onion looked like. The inference which is drawn from the comprehension of one term in a comparison to the comprehension of the other is one of the most important reasons for the occurrence of so many misunderstandings. The example, as such, is understood, but its application to the assertion and the question whether the latter is also made clear by the example are forgotten. This explains the well known and supreme power of examples and comparisons, and hence the wise of all times have used comparisons in speaking to the poor in spirit. Hence, too, the great effect of comparisons, and also the numerous and coarse misunderstandings and the effort of the untrained and unintelligent to clarify those things they do not understand by means of comparisons. Fortunately they have, in trying to explain the thing to other people, the habit of making use of these difficultly discovered comparisons so that the others, if they are only sufficiently observant, may succeed in testing the correctness of the inference from one term in a comparison to the other. We do this frequently in examining witnesses, and we discover that the witness has made use of a figure to clarify some unintelligible point and that he necessarily understands it since it lies within the field of his instruments of thought. But what is compared remains as confused to him as before. The test of it, therefore, is very tiring and mainly without results, because one rarely succeeds in liberating a man from some figure discovered with difficulty. He always returns to it because he understands it, though really not what he compares. But what is gained in such a case is not little, for the certainty that, so revealed, the witness does not understand the matter in hand, easily determines the value of his testimony.
The fullness of the possibilities under which anything may be asserted is also of importance in this matter. The inference that a thing is impossible is generally made by most people in such wise that they first consider the details of the eventualities they already know, or immediately present. Then, when these are before them, they infer that the matter is quite impossible—and whether one or more different eventualities have missed of consideration, is not studied at all. Our kindly professor of physics once told us: "Today I intended to show you the beautiful experiments in the interference of light—but it can not be observed in daylight and when I draw the curtains you raise rough-house. The demonstration is therefore impossible and I take the instruments away.'' The good man did not consider the other eventuality, that we might be depended upon to behave decently even if the curtains were drawn.
Hence the rule that a witness's assertion that a thing is impossible must never be trusted. Take the simplest example. The witness assures us that it is impossible for a theft to have been committed by some stranger from outside. If you ask him why, he will probably tell you: "Because the door was bolted and the windows barred.'' The eventuality that the thief might have entered by way of the chimney, or have sent a child between the bars of the window, or have made use of some peculiar instrument, etc., are not considered, and would not be if the question concerning the ground of the inference had not been put.
We must especially remember that we criminalists "must not dally with mathematical truth but must seek historical truth. We start with a mass of details, unite them, and succeed by means of this union and test in attaining a result which permits us to judge concerning the existence and the characteristics of past events.'' The material of our work lies in the mass of details, and the manner and reliability of its presentation determines the certainty of our inferences.
Seen more closely the winning of this material may be described as Hume describes it: "If we would satisfy ourselves, therefore, concerning the nature of that evidence which assures us of matters of fact, we must inquire how we arrive at the knowledge of cause and effect. I shall venture to affirm as a general proposition which admits of no exception, that the knowledge of this relation is not, in any instance, attained by reasonings a priori; but arises entirely from experience, when we find that any particular objects are constantly conjoined with each other; . . . nor can our reason, unassisted by experience, ever draw any inference concerning real existence and matter of fact.''
 David Hume: Enquiry, p. 33 (Open Court Ed.).
In the course of his explanation Hume presents two propositions,
(1) I have found that such an object has always been attended with such an effect.
(2) I foresee that other objects which are in appearance similar, will be attended with similar effects.
He goes on: "I shall allow, if you please, that the one proposition may justly be inferred from the other; I know in fact that it always is inferred. But if you insist that the inference is made by a chain of reasoning, I desire you to produce that chain of reasoning. The connection between these propositions is not intuitive. There is required a medium which may enable the mind to draw such an inference, if, indeed, it be drawn by reasoning and argument. What the medium is, I must confess, passes my comprehension; and it is incumbent on those to produce it who assert that it exists, and is the origin of all our conclusions concerning matters of fact.''
If we regard the matter more closely we may say with certainty: This medium exists not as a substance but as a transition. When I speak in the proposition of "such an object,'' I already have "similar'' in mind, inasmuch as there is nothing absolutely like anything else, and when I say in the first proposition, "such an object,'' I have already passed into the assertion made in the second proposition.
Suppose that we take these propositions concretely:
(1) I have discovered that bread made of corn has a nourishing effect.
(2) I foresee that other apparently similar objects, e. g., wheat, will have a like effect.
I could not make various experiments with the same corn in case (1). I could handle corn taken as such from one point of view, or considered as such from another, i. e., I could only experiment with very similar objects. I can therefore make these experiments with corn from progressively remoter starting points, or soils, and finally with corn from Barbary and East Africa, so that there can no longer be any question of identity but only of similarity. And finally I can compare two harvests of corn which have less similarity than certain species of corn and certain species of wheat. I am therefore entitled to speak of identical or similar in the first proposition as much as in the second. One proposition has led into another and the connection between them has been discovered.
The criminological importance of this "connection'' lies in the fact that the correctness of our inferences depends upon its discovery. We work continuously with these two Humian propositions, and we always make our assertion, first, that some things are related as cause and effect, and we join the present case to that because we consider it similar. If it is really similar, and the connection of the first and the second proposition are actually correct, the truth of the inference is attained. We need not count the unexplained wonders of numerical relations in the result. D'Alembert asserts: "It seems as if there were some law of nature which more frequently prevents the occurrence of regular than irregular combinations; those of the first kind are mathematically, but not physically, more probable. When we see that high numbers are thrown with some one die, we are immediately inclined to call that die false.'' And John Stuart Mill adds, that d'Alembert should have set the problem in the form of asking whether he would believe in the die if, after having examined it and found it right, somebody announced that ten sixes had been cast with it.
We may go still further and assert that we are generally inclined to consider an inference wrong which indicates that accidental matters have occurred in regular numerical relation. Who believes the hunter's story that he has shot 100 hares in the past week, or the gambler's that he has won 1000 dollars; or the sick man's, that he was sick ten times? It will be supposed at the very least that each is merely indicating an approximately round sum. Ninety-six hares, 987 dollars, and eleven illnesses will sound more probable. And this goes so far that during examinations, witnesses are shy of naming such "improbable ratios,'' if they at all care to have their testimony believed. Then again, many judges are in no wise slow to jump at such a number and to demand an "accurate statement,'' or eves immediately to decide that the witness is talking only "about.'' How deep-rooted such views are is indicated by the circumstance that bankers and other merchants of lottery tickets find that tickets with "pretty numbers'' are difficult to sell. A ticket of series 1000, number 100 is altogether unsalable, for such a number "can not possibly be sold.'' Then again, if one has to count up a column of accidental figures and the sum is 1000, the correctness of the sum is always doubted.
Here are facts which are indubitable and unexplained. We must therefore agree neither to distrust so-called round numbers, nor to place particular reliance on quite irregular figures. Both should be examined.
It may be that the judgment of the correctness of an inference is made analogously to that of numbers and that the latter exercise an influence on the judgment which is as much conceded popularly as it is actually combated. Since Kant, it has been quite discovered that the judgment that fools are in the majority must lead through many more such truths in judging—and it is indifferent whether the judgment dealt with is that of the law court or of a voting legislature or mere judgments as such.
Schiel says, "It has been frequently asserted that a judgment is more probably correct according to the number of judges and jury. Quite apart from the fact that the judge is less careful, makes less effort, and feels less responsibility when he has associates, this is a false inference from an enormous average of cases which are necessarily remote from any average whatever. And when certain prejudices or weaknesses of mind are added, the mistake multiplies. Whoever accurately follows, if he can avoid getting bored, the voting of bodies, and considers by themselves individual opinions about the subject, they having remained individual against large majorities and hence worthy of being subjected to a cold and unprejudiced examination, will learn some rare facts. It is especially interesting to study the judgment of the full bench with regard to a case which has been falsely judged; surprisingly often only a single individual voice has spoken correctly. This fact is a warning to the judge in such cases carefully to listen to the individual opinion and to consider that it is very likely to deserve study just because it is so significantly in the minority.
The same thing is to be kept in mind when a thing is asserted by a large number of witnesses. Apart from the fact that they depend upon one another, that they suggest to one another, it is also easily possible, especially if any source of error is present, that the latter shall have influenced all the witnesses.
Whether a judgment has been made by a single judge or is the verdict of any number of jurymen is quite indifferent since the correctness of a judgment does not lie in numbers. Exner says, "The degree of probability of a judgment's correctness depends upon the richness of the field of the associations brought to bear in establishing it. The value of knowledge is judicially constituted in this fact, for it is in essence the expansion of the scope of association. And the value is proportional to the richness of the associations between the present fact and the knowledge required.'' This is one of the most important of the doctrines we have to keep in mind, and it controverts altogether those who suppose that we ought to be satisfied with the knowledge of some dozens of statutes, a few commentaries, and so and so many precedents.
If we add that "every judgment is an identification and that in every judgment we assert that the content represented is identical in spite of two different associative relationships,'' it must become clear what dangers we undergo if the associative relationships of a judge are too poor and narrow. As Mittermaier said seventy years ago: "There are enough cases in which the weight of the evidence is so great that all judges are convinced of the truth in the same way. But in itself what determines the judgment is the essential character of him who makes it.'' What he means by essential character has already been indicated.
 H. Mnsterberg: Beitrge zur experimentellen Psychologie, III. Freiburg.
We have yet to consider the question of the value of inferences made by a witness from his own combinations of facts, or his descriptions. The necessity, in such cases, of redoubled and numerous examinations is often overlooked. Suppose, for example, that the witness does not know a certain important date, but by combining what he does know, infers it to have been the second of June, on which day the event under discussion took place. He makes the inference because at the time he had a call from A, who was in the habit of coming on Wednesdays, but there could be no Wednesday after June seventh because the witness had gone on a long journey on that day, and it could not have been May 26 because this day preceded a holiday and the shop was open late, a thing not done on the day A called. Nor, moreover, could the date have been May 20, because it was very warm on the day in question, and the temperature began to rise only after May 20. In view of these facts the event under discussion must have occurred upon June 2nd and only on that day.
As a rule, such combinations are very influential because they appear cautious, wise and convincing. They impose upon people without inclination toward such processes. More so than they have a right to, inasmuch as they present little difficulty to anybody who is accustomed to them and to whom they occur almost spontaneously. As usually a thing that makes a great impression upon us is not especially examined, but is accepted as astounding and indubitable, so here. But how very necessary it is carefully to examine such things and to consider whether the single premises are sound, the example in question or any other example will show. The individual dates, the facts and assumptions may easily be mistaken, and the smallest oversight may render the result false, or at least not convincing.
The examination of manuscripts is still more difficult. What is written has a certain convincing power, not only on others but on the writer, and much as we may be willing to doubt and to improve what has been written immediately or at most a short time ago, a manuscript of some age has always a kind of authority and we give it correctness cheaply when that is in question. In any event there regularly arises in such a case the problem whether the written description is quite correct, and as regularly the answer is a convinced affirmative. It is impossible to give any general rule for testing such affirmation. Ordinarily some clearness may be attained by paying attention to the purpose of the manuscript, especially in order to ascertain its sources and the personality of the writer. There is much in the external form of the manuscript. Not that especial care and order in the notes are particularly significant; I once published the accounts of an old peasant who could neither read nor write, and his accounts with a neighbor were done in untrained but very clear fashion, and were accepted as indubitable in a civil case. The purposiveness, order, and continuity of a manuscript indicate that it was not written after the event; and are therefore, together with the reason for having written it and obviously with the personality of the writer, determinative of its value.
Section 32. (j) Mistaken Inferences.
It is true, as Huxley says, that human beings would have made fewer mistakes if they had kept in mind their tendency to false judgments which depend upon extraordinary combinations of real experiences. When people say: I felt, I heard, I saw this or that, in 99 cases out of 100 they mean only that they have been aware of some kind of sensation the nature of which they determine in a *judgment. Most erroneous inferences ensue in this fashion. They are rarely formal and rarely arise by virtue of a failure to use logical principles; their ground is the inner paucity of a premise, which itself is erroneous because of an erroneous perception or conception. As Mill rightly points out, a large portion of mankind make mistakes because of tacit assumptions that the order of nature and the order of knowledge are identical and that things must exist as they are thought, so that when two things can not be thought together they are supposed not to exist together, and the inconceivable is supposed to be identical with the non-existent. But what they do not succeed in conceiving must not be confused with the absolutely inconceivable. The difficulty or impossibility of conceiving may be subjective and conditional, and may prevent us from understanding the relation of a series of events only because some otherwise proxi- mate condition is unknown or overlooked. Very often in criminal cases when I can make no progress in some otherwise simple matter, I recall the well known story of an old peasant woman who saw the tail of a horse through an open stable door and the head of another through another door several yards away, and because the colors of both head and tail were similar, was moved to cry out: "Dear Lord, what a long horse!'' The old lady started with the presupposition that the rump and the head of the two horses belonged to one, and could make no use of the obvious solution of the problem of the inconceivably long horse by breaking it in two.
 Cf. O. Gross: Soziale Hemmungsvorstellungen. II Gross's Archiv: VII, 123.
Such mistakes may be classified under five heads.
 A paragraph is here omitted. Translator.
(1) Aprioristic mistakes. (Natural prejudices).
(2) Mistakes in observation.
(3) Mistakes in generalization. (When the facts are right and the inferences wrong).
(4) Mistakes of confusion. (Ambiguity of terms or mistakes by association).
(5) Logical fallacies.
All five fallacies play important rles in the lawyer's work.
We have very frequently to fight natural prejudices. We take certain classes of people to be better and others to be worse than the average, and without clearly expressing it we expect that the first class will not easily do evil nor the other good. We have prejudices about some one or another view of life; some definition of justice, or point of view, although we have sufficient opportunity to be convinced of their incorrectness. We have a similar prejudice in trusting our human knowledge, judgment of impressions, facts, etc., far too much, so far indeed, that certain relations and accidents occurring to any person we like or dislike will determine his advantage or disadvantage at our hands.
Of importance under this heading, too, are those inferences which are made in spite of the knowledge that the case is different; the power of sense is more vigorous than that of reflection. As Hartmann expresses it: "The prejudices arising from sensation, are not conscious judgments of the understanding but instinctively practical postulates, and are, therefore, very difficult to destroy, or even set aside by means of conscious consideration. You may tell yourself a thousand times that the moon at the horizon is as big as at the zenith—nevertheless you see it smaller at the zenith.'' Such fixed impressions we meet in every criminal trial, and if once we have considered how the criminal had committed a crime we no longer get free of the impression, even when we have discovered quite certainly that he had no share in the deed. The second type of fallacy—mistakes in observation—will be discussed later under sense perception and similar matters.
Under mistakes of generalization the most important processes are those of arrangement, where the environment or accompanying circumstances exercise so determinative an influence that the inference is often made from them alone and without examination of the object in question. The Tanagra in the house of an art-connoisseur I take to be genuine without further examination; the golden watch in the pocket of a tramp to be stolen; a giant meteor, the skeleton of an iguana, a twisted-looking Nerva in the Royal Museum of Berlin, I take to be indubitably original, and indubitably imitations in the college museum of a small town. The same is true of events: I hear a child screeching in the house of the surly wife of the shoemaker so I do not doubt that she is spanking it; in the mountains I infer from certain whistles the presence of chamois, and a single long drawn tone that might be due to anything I declare to have come from an organ, if a church is near by.
All such processes are founded upon experience, synthesis, and, if you like, prejudices. They will often lead to proper conclusions, but in many cases they will have the opposite effect. It is a frequently recurring fact that in such cases careful examination is most of all necessary, because people are so much inclined to depend upon "the first, always indubitably true impression.'' The understanding has generalized simply and hastily, without seeking for justification.
The only way of avoiding great damage is to extract the fact in itself from its environment and accompanying circumstance, and to study it without them. The environment is only a means of proof, but no proof, and only when the object or event has been validated in itself may we adduce one means of proof after another and modify our point of view accordingly. Not to do so, means always to land upon false inferences, and what is worse, to find it impossible upon the recognition of an error later on, to discover at what point it has occurred. By that time it has been buried too deep in the heap of our inferential system to be discoverable.
The error of confusion Mill reduces especially to the unclear representation of *what proof is, i. e., to the ambiguity of words. We rarely meet such cases, but when we do, they occur after we have compounded concepts and have united rather carelessly some symbol with an object or an event which ought not to have been united, simply because we were mistaken about its importance. A warning example may be found in the inference which is made from the sentence given a criminal because of "identical motive.'' The Petitio, the Ignorantia, etc., belong to this class. The purely logical mistakes or mistakes of syllogism do not enter into these considerations.
Section 33. (k) Statistics of the Moral Situation.
Upon the first glance it might be asserted that statistics and psychology have nothing to do with each other. If, however, it is observed that the extraordinary and inexplicable results presented by statistics of morals and general statistics influence our thought and reflection unconditionally, its importance for criminal psychology can not be denied. Responsibility, abundance of criminals, their distribution according to time, place, personality, and circumstances, the regularity of their appearance, all these have so profound an influence upon us both essentially and circumstantially that even our judgments and resolutions, no less than the conduct and thought of other people whom we judge, are certainly altered by them. Moreover, probability and statistics are in such close and inseparable connection that we may not make use of or interpret the one without the other. Eminent psychological contributions by Mnsterberg show the importance the statistical problems have for psychology. This writer warns us against the over-valuation of the results of the statistics of morality, and believes that its proper tendencies will be discovered only much later. In any event the real value of statistical synthesis and deduction can be discovered only when it is closely studied. This is particularly true with regard to criminal conditions. The works of many authors teach us things that would not otherwise be learned, and they would not be dealt with here if only a systematic study of the works themselves could be of use. We speak here only of their importance for our own discipline. Nobody doubts that there are mysteries in the figures and figuring of statistics. We admit honestly that we know no more to-day than when Paul de Decker discussed Quetelet's labors in statistics of morality in the Brussels Academy of Science, and confessed what a puzzle it was that human conduct, even in its smallest manifestations, obeyed in their totality constant and immutable laws. Concerning this curious fact Adolf Wagner says: "If a traveler had told us something about some people where a statute determines exactly how many persons per year shall marry, die, commit suicide, and crimes within certain classes,—and if he had announced furthermore that these laws were altogether obeyed, what should we have said? And as a matter of fact the laws are obeyed all the world over.''
 O. Gross: Zur Phyllogenese der Ethik. H. Gross's Archiv, IX, 100.  Cf. B. Foldes: Einuge Ergebnisse der neueren Kriminalstatistik. Zeitschrift f. d. yes. Strafrechte-Wissenschaft, XI. 1891.  Ncke: Moralische Werte. Archiv, IX, 213
Of course the statistics of morality deal with quantities not qualities, but in the course of statistical examination the latter are met with. So, e. g., examinations into the relation of crime to school- attendance and education, into the classes that show most suicides, etc., connect human qualities with statistical data. The time is certainly not far off when we shall seek for the proper view of the probability of a certain assumption with regard to some rare crime, doubtful suicide, extraordinary psychic phenomena, etc., with the help of a statistical table. This possibility is made clearer when the inconceivable constancy of some figures is considered. Suppose we study the number of suicides since 1819 in Austria, in periods of eight years. We find the following figures, 3000, 5000, 6000, 7000, 9000, 12000, 15000—i. e., a regular increase which is comparable to law. Or suppose we consider the number of women, who, in the course of ten continuous years in France, shot themselves; we find 6, 6, 7, 7, 6, 6, 7; there is merely an alternation between 6 and 7. Should not we look up if in some one year eight or nine appeared? Should not we give some consideration to the possibility that the suicide is only a pretended one? Or suppose we consider the number of men who have drowned themselves within the same time: 280, 285, 292, 276, 257, 269, 258, 276, 278, 287,—Wagner says rightly of such figures "that they contain the arithmetical relation of the mechanism belonging to a moral order which ought to call out even greater astonishment than the mechanism of stellar systems.''
 J. Gurnhill: The Morals of Suicide. London 1900.
Still more remarkable are the figures when they are so brought together that they may be seen as a curve. It is in this way that Drobisch brings together a table which distributes crime according to age. Out of a thousand crimes committed by persons between the ages of: —————————————————————— AGAINST AGAINST PROPERTY PERSONS Less than 16 years 2 0.53
16-21 105 28
21-25 114 50
25-30 101 48
30 35 93 41
35-40 78 31
40-45 63 25
45-50 48 19
50-55 34 15
55-60 24 12
60 65 19 11
65-70 14 8
70-80 8 5 More than 80 2 2 ———————————————————————-
Through both columns a definite curve may be drawn which grows steadily and drops steadily. Greater mathematical certainty is almost unthinkable. Of similar great importance is the parallelization of the most important conditions. When, e. g., suicides in France, from 1826 to 1870 are taken in series of five years we find the figures 1739, 2263, 2574, 2951, 8446, 3639, 4002, 4661, 5147; if now during that period the population has increased from 30 to only 36 millions other determining factors have to be sought.
 Ncke in Archiv VI, 325, XIV, 366.
Again, most authorities as quoted by Gutberlet, indicate that most suicides are committed in June, fewest in December; most at night, especially at dawn, fewest at noon, especially between twelve and two o'clock. The greatest frequency is among the half-educated, the age between sixty and seventy, and the nationality Saxon (Oettingen).
 K. Gutberlet: Die Willensfreiheit u. ihre Gegner. Fulda 1893.
The combination of such observations leads to the indubitable conclusion that the results are sufficiently constant to permit making at least an assumption with regard to the cases in hand. At present, statistics say little of benefit with regard to the individual; J. S. Mill is right in holding that the death-rate will help insurance companies but will tell any individual little concerning the duration of his life. According to Adolf Wagner, the principal statistical rule is: The law has validity when dealing with great numbers; the constant regularity is perceivable only when cases are very numerous; single cases show many a variation and exception. Quetelet has shown the truth of this in his example of the circle. "If you draw a circle on the blackboard with thick chalk, and study its outline closely in small sections, you will find the coarsest irregularities; but if you step far back and study the circle as a whole, its regular, perfect form becomes quite distinct.'' But the circle must be drawn carefully and correctly, and one must not give way to sentimentality and tears when running over a fly's legs in drawing. Emil du Bois-Reymond says against this: "When the postmaster announces that out of 100,000 letters a year, exactly so and so many come unaddressed, we think nothing of the matter—but when Quetelet counts so and so many criminals to every 100,000 people our moral sense is aroused since it is painful to think that *we are not criminals simply because somebody else has drawn the black spot.'' But really there is as little regrettable in this fact as in the observation that every year so and so many men break their legs, and so and so many die—in those cases also, a large number of people have the good fortune not to have broken their legs nor to have died. We have here the irrefutable logic of facts which reveals nothing vexatious.
 Die sieben Weltrtsel. Leipzig 1882.
On the other hand, there is no doubt that our criminal statistics, to be useful, must be handled in a rather different fashion. We saw, in studying the statistics of suicide, that inferences with regard to individual cases could be drawn only when the material had been studied carefully and examined on all sides. But our criminological statistic is rarely examined with such thoroughness; the tenor of such examination is far too bureaucratic and determined by the statutes and the process of law. The criminalist gives the statistician the figures but the latter can derive no significant principles from them. Consider for once any official report on the annual results in the criminal courts in any country. Under and over the thousands and thousands of figures and rows of figures there is a great mass of very difficult work which has been profitable only in a very small degree. I have before me the four reports of a single year which deal with the activities of the Austrian courts and criminal institutions, and which are excellent in their completeness, correctness, and thorough revision. Open the most important,—the results of the administration of criminal law in the various departments of the country,—and you find everything recorded:—how many were punished here and how many there, what their crimes were, the percentage of condemned according to age, social standing, religion, occupation, wealth, etc.; then again you see endless tables of arrests, sentences, etc., etc. Now the value of all this is to indicate merely whether a certain regularity is discoverable in the procedure of the officials. Material psychologically valuable is rare. There is some energetic approximation to it in the consideration of culture, wealth, and previous sentences, but even these are dealt with most generally, while the basis and motive of the death-sentence is barely indicated. We can perceive little consideration of motives with regard to education, earlier life, etc., in their relation to sentencing. Only when statistics will be made to deal actually and in every direction with qualities and not merely with quantities will they begin to have a really scientific value.
Topic II. KNOWLEDGE. Section 34.
Criminal law, like all other disciplines, must ask under what conditions and when we are entitled to say "we know.'' The answer is far from being perennially identical, though it might have been expected that the conviction of knowledge would be ever united with identical conditions. The strange and significant difference is determined by the question whether the verdict, "we know,'' will or will not have practical consequences. When we discuss some question like the place of a certain battle, the temperature of the moon, or the appearance of a certain animal in the Pliocene, we first assume that there *is a true answer; reasons for and against will appear, the former increase in number, and suddenly we discover in some book the assurance that, "We know the fact.'' That assurance passes into so and so many other books; and if it is untrue, no essential harm can be done.
But when science is trying to determine the quality of some substance, the therapeutic efficiency of some poison, the possibilities of some medium of communication, the applicability of some great national economic principle like free trade, then it takes much more time to announce, "We know that this is so and not otherwise.'' In this case one sees clearly that tremendous consequences follow on the practical interpretation of "we know,'' and therefore there is in these cases quite a different taxation of knowledge from that in cases where the practical consequences are comparatively negligible.
Our work is obviously one of concrete practical consequences. It contains, moreover, conditions that make imperfect knowledge equivalent to complete ignorance, for in delivering sentence every "no'' may each time mean, "We know that he has not done it'' or again, "We know that it is not altogether certain that he has done it.'' Our knowledge in such cases is limited to the recognition of the confusion of the subject, and knowledge in its widest sense is the consciousness of some definite content; in this case, confusion. Here, as everywhere, knowledge is not identical with truth; knowledge is only subjective truth. Whoever knows, has reasons for considering things true and none against so considering them. Here, he is entitled to assume that all who recognize his knowledge will justify it. But, when even everybody justifies his knowledge, it can be justified only in its immediacy; to-morrow the whole affair may look different. For this reason we criminalists assert much less than other investigators that we seek the truth; if we presume to such an assertion, we should not have the institutions of equity, revision, and, in criminal procedure, retrial. Our knowledge, when named modestly, is only the innermost conviction that some matter is so and so according to human capacity, and "such and such a condition of things.'' Parenthetically, we agree that "such and such a condition of things'' may alter with every instant and we declare ourselves ready to study the matter anew if the conditions change. We demand material, but relative truth.
One of the acutest thinkers, J. R. von Mayer, the discoverer of the working principle of "conservation of energy,'' says, "the most important, if not the only rule for real natural science is this: Always to believe that it is our task to know the phenomena before we seek explanation of higher causes. If a fact is once known in all its aspects, it is thereby explained and the duty of science fulfilled.'' The author did not have us dry-souled lawyers in mind when he made this assertion, but we who modestly seek to subordinate our discipline to that of the correct one of natural science, must take this doctrine absolutely to heart. Every crime we study is a fact, and once we know it in all its aspects and have accounted for every little detail, we have explained it and have done our duty.
But the word explain does not lead us very far. It is mainly a matter of reducing the mass of the inexplicable to a minimum and the whole to its simplest terms. If only we succeed in this reduction! In most cases we substitute for one well-known term, not another still better one, but a strange one which may mean different things to different people. So again, we explain one event by means of another more difficult one. It is unfortunate that we lawyers are more than all others inclined to make unnecessary explanations, because our criminal law has accustomed us to silly definitions which rarely bring us closer to the issue and which supply us only with a lot of words difficult to understand instead of easily comprehensible ones. Hence we reach explanations both impossible and hard to make, explanations which we ourselves are often unwilling to believe. And again we try to explain and to define events which otherwise would have been understood by everybody and which become doubtful and uncertain because of the attempt. The matter becomes especially difficult when we feel ourselves unsure, or when we have discovered or expect contradiction. Then we try to convince ourselves that we know something, although at the beginning we were clearly enough aware that we knew nothing. We must not forget that our knowledge can attain only to ideas of things. It consists alone in the perception of the relation and agreement, or in the incompatibility and contradiction of some of our ideas. Our task lies exactly in the explication of these impressions, and the more thoroughly that is done the greater and more certain is the result. But we must never trust our own impressions merely. "When the theologian, who deals with the supersensible, has said all that, from his point of view, he can say, when the jurist, who represents those fundamental laws which are the result of social experience, has considered all reasons from his own point of view, the final authority in certain cases must be the physician who is engaged in studying the life of the body.''
I get this from Maudsley, and it leads us to keep in mind that our knowledge is very one-sided and limited, and that an event is known only when all have spoken who possess especial knowledge of its type. Hence, every criminalist is required to found his knowledge upon that of the largest possible number of experts and not to judge or discuss any matter which requires especial information without having first consulted an expert with regard to it. Only the sham knows everything; the trained man understands how little the mind of any individual may grasp, and how many must coperate in order to explain the very simplest things.
 Henry Maudsley: Physiology and Pathology of the Mind.
The complexity of the matter lies in the essence of the concept "to be.'' We use the word "to be'' to indicate the intent of all perceived and perceivable. " 'To be' and 'to know' are identical in so far as they have identical content, and the content may be known?''
 Jessen: Versuch einer wissenschaftlichen Begrndung der Psychologie. Berlin 1855.
OBJECTIVE CONDITIONS OF CRIMINAL INVESTIGATION: THE MENTAL ACTIVITY OF THE EXAMINEE.
TITLE A. GENERAL CONDITIONS.
Topic I. OF SENSE-PERCEPTION.
Our conclusions depend upon perceptions made by ourselves and others. And if the perceptions are good our judgments *may be good, if they are bad our judgments *must be bad. Hence, to study the forms of sense-perception is to study the fundamental conditions of the administration of law, and the greater the attention thereto, the more certain is the administration.
It is not our intention to develop a theory of perception. We have only to extract those conditions which concern important circumstances, criminologically considered, and from which we may see how we and those we examine, perceive matters. A thorough and comprehensive study of this question can not be too much recommended. Recent science has made much progress in this direction, and has discovered much of great importance for us. To ignore this is to confine oneself merely to the superficial and external, and hence to the inconceivable and incomprehensible, to ignoring valuable material for superficial reasons, and what is worse, to identifying material as important which properly understood has no value whatever.
Section 36. (a) General Considerations.
The criminalist studies the physiological psychology of the senses and their functions, in order to ascertain their nature, their influence upon images and concepts, their trustworthiness, their reliability and its conditions, and the relation of perception to the object. The question applies equally to the judge, the jury, the witness, and the accused. Once the essence of the function and relation of sense-perception is understood, its application in individual cases becomes easy.
 For a general consideration of perception see James, Principles of Psychology. Angell, Psychology.
The importance of sense-perception need not be demonstrated. "If we ask,'' says Mittermaier, "for the reason of our conviction of the truth of facts even in very important matters, and the basis of every judgment concerning existence of facts, we find that the evidence of the senses is final and seems, therefore, the only true source of certainty.''
There has always, of course, been a quarrel as to the objectivity and reliability of sense-perception. That the senses do not lie, "not because they are always correct, but because they do not judge,'' is a frequently quoted sentence of Kant's; the Cyrenaics have already suggested this in asserting that pleasure and pain alone are indubitable. Aristotle narrows the veracity of sensation to its essential content, as does Epicurus. Descartes, Locke and Leibnitz have suggested that no image may be called, as mere change of feeling, true or false. Sensationalism in the work of Gassendi, Condillac, and Helvetius undertook for this reason the defense of the senses against the reproach of deceit, and as a rule did it by invoking the infallibility of the sense of touch against the reproach of the contradictions in the other senses. Reid went back to Aristotle in distinguishing specific objects for each sense and in assuming the truth of each sense within its own field.
That these various theories can be adjusted is doubtful, even if, from a more conservative point of view, the subject may be treated quantitatively. The modern quantification of psychology was begun by Herbart, who developed a mathematical system of psychology by introducing certain completely unempirical postulates concerning the nature of representation and by applying certain simple premises in all deductions concerning numerical extent. Then came Fechner, who assumed the summation of stimuli. And finally these views were determined and fixed by the much-discussed Weber's Law, according to which the intensity of the stimulus must increase in the proportion that the intensity of the sensation is to increase; i. e., if a stimulus of 20 units requires the addition of 3 before it can be perceived, a stimulus of 60 units would require the addition of 9. This law, which is of immense importance to criminalists who are discussing the sense-perceptions of witnesses, has been thoroughly and conclusively dealt with by A. Meinong.
 Meinong: ber die Bedeutung der Weberschen Gesetzes. Hamburg and Leipzig, 1896.
"Modern psychology takes qualities perceived externally to be in themselves subjective but capable of receiving objectivity through our relation to the outer world.... The qualitative character of our sensory content produced by external stimuli depends primarily on the organization of our senses. This is the fundamental law of perception, of modern psychology, variously expressed, but axiomatic in all physiological psychology.'' In this direction Helmholtz has done pioneer work. He treats particularly the problem of optics, and physiological optics is the study of perception by means of the sense of sight. We see things in the external world through the medium of light which they direct upon our eyes. The light strikes the retina, and causes a sensation. The sensation brought to the brain by means of the optic nerve becomes the condition of the representation in consciousness of certain objects distributed in space.... We make use of the sensation which the light stimulates in the mechanism of the optic nerve to construct representations concerning the existence, form, and condition of external objects. Hence we call images perceptions of sight. (Our sense-perception, according to this theory, consists, therefore, entirely of sensations; the latter constitute the stuff or the content from which the other is constructed). Our sensations are effects caused in our organs, externally, and the manifestation of such an effect depends essentially upon the nature of the apparatus which has been stimulated.
 T. Pesch Das Weltphnomen
 H. Helmholtz: Die Tatsachen der Wahrnehmung. Braunsehweig 1878.
There are certain really known inferences, e. g., those made by the astronomer from the perspective pictures of the stars to their positions in space. These inferences are founded upon well- studied knowledge of the principles of optics. Such knowledge of optics is lacking in the ordinary function of seeing; nevertheless it is permissible to conceive the psychical function of ordinary perception as unconscious inferences, inasmuch as this name will completely distinguish them from the commonly so-called conscious inferences.
The last-named condition is of especial importance to us. We need investigation to determine the laws of the influence of optical and acoustical knowledge upon perception. That these laws are influential may be verified easily. Whoever is ignorant, e. g., that a noise is reflected back considerably, will say that a wagon is turning from the side from which the noise comes, though if he knows the law, if he knows that fact, his answer would be reversed. So, as every child knows that the reflection of sound is frequently deceptive, everybody who is asked in court will say that he believes the wagon to be on the right side though it might as well have been on the left. Again, if we were unaware that light is otherwise refracted in water than in air we could say that a stick in the water has been bent obtusely, but inasmuch as everybody knows this fact of the relation of light to water, he will declare that the stick appears bent but really is straight.
From these simplest of sense-perceptions to the most complicated, known only to half a dozen foremost physicists, there is an infinite series of laws controlling each stage of perception, and for each stage there is a group of men who know just so much and no more. We have, therefore, to assume that their perceptions will vary with the number and manner of their accomplishments, and we may almost convince ourselves that each examinee who has to give evidence concerning his sense-perception should literally undergo examination to make clear his scholarly status and thereby the value of his testimony. Of course, in practice this is not required. First of all we judge approximately a man's nature and nurture and according to the impression he makes upon us, thence, his intellectual status. This causes great mistakes. But, on the other hand, the testimony is concerned almost always with one or several physical events, so that a simple relational interrogation will establish certainly whether the witness knows and attends to the physical law in question or not. But anyway, too little is done to determine the means a man uses to reach a certain perception. If instantaneous contradictions appear, there is little damage, for in the absence of anything certain, further inferences are fortunately made in rare cases only. But when the observation is that of one person alone, or even when more testify but have accidentally the same amount of knowledge and hence have made the same mistake, and no contradiction appears, we suppose ourselves to possess the precise truth, confirmed by several witnesses, and we argue merrily on the basis of it. In the meantime we quite forget that contradictions are our salvation from the trusting acceptance of untruth— and that the absence of contradiction means, as a rule, the absence of a starting point for further examination.
For this reason and others modern psychology requires us to be cautious. Among the others is the circumstance that perceptions are rarely pure. Their purity consists in containing nothing else than perception; they are mixed when they are connected with imaginations, judgments, efforts, and volitions. How rarely a perception is pure I have already tried to show; judgments almost always accompany it. I repeat too, that owing to this circumstance and our ignorance of it, countless testimonies are interpreted altogether falsely. This is true in many other fields. When, for example, A. Fick says: "The condition we call sensation occurs in the consciousness of the subject when his sensory nerves are stimulated,'' he does not mean that the nervous stimulus in itself is capable of causing the condition in question. This one stimulus is only a single tone in the murmur of countless stimuli, which earlier and at the same time have influenced us and are different in their effect on each man. Therefore, that single additional tone will also be different in each man. Or, when Bernstein says that "Sensation, i. e., the stimulation of the sensorium and the passage of this stimulation to the brain, does not in itself imply the perception of an object or an event in the external world,'' we gather that the objectivity of the perception works correctively not more than one time out of many. So here again everything depends upon the nature and nurture of the subject.
Sensations are, according to Aubert, still more subjective. "They are the specific activity of the sense organs, (not, therefore, passive as according to Helmholtz, but active functions of the sense organs). Perception arises when we combine our particular sensations with the pure images of the spirit or the schemata of the understanding, especially with the pure image of space. The so-called ejection or externalization of sensations occurs only as their scheme and relation to the unity of their object.''
So long as anything is conceived as passive it may always recur more identically than when it is conceived as active. In the latter case the individuality of the particular person makes the perception in a still greater degree individual, and makes it almost the creature of him who perceives. Whether Aubert is right or not is not our task to discover, but if he is right then sense-perception is as various as is humanity. The variety is still further increased by means of the comprehensive activity which Fischer presupposes. "Visual perception has a comprehensive or compounding activity. We never see any absolute simple and hence do not perceive the elements of things. We see merely a spatial continuum, and that is possible only through comprehensive activity—especially in the case of movement in which the object of movement and the environment must both be perceived.'' But each individual method of "comprehension'' is different. And it is uncertain whether this is purely physical, whether only the memory assists (so that the attention in biased by what has been last perceived), whether imagination is at work or an especial psychical activity must be presupposed in compounding the larger elements. The fact is that men may perceived an enormous variety of things with a single glance. And generally the perceptive power will vary with the skill of the individual. The narrowest, smallest, most particularizing glance is that of the most foolish; and the broadest, most comprehensive, and comparing glance, that of the most wise. This is particularly noticeable when the time of observation is short. The one has perceived little and generally the least important; the other has in the same time seen everything from top to bottom and has distinguished between the important and the unimportant, has observed the former rather longer than the latter, and is able to give a better description of what he has seen. And then, when two so different descriptions come before us, we wonder at them and say that one of them is untrue.[1b]
 E. L. Fischer: Theorie der Gesichtswahrnehmung. Mainz 1891.
[1b] Cf. Archiv, XVI, 371.
The speed of apperception has been subjected to measurement by Auerbach, Kries, Baxt, von Tigerstedt and Bergqvist, Stern, Vaschide, Vurpass, etc. The results show 0.015 to 0.035 seconds for compounded images. Unfortunately, most of these experiments have brought little unanimity in the results and have not compared, e. g., the apperception-times of very clever people with those of very slow and stupid ones. In the variety of perception lies the power of presentation (in our sense of the term). In the main other forces assist in this, but when we consider how the senses work in combination we must conclude that they determine their own forms. "If we are to say that sense experience instructs us concerning the manifoldness of objects we may do so correctly if we add the scholium that many things could not be mentioned without synthesis.'' So Drner writes. But if we approach the matter from another side, we see how remarkable it is that human perceptions can be compared at all. Hermann Schwarz says "According to the opinion of the physicists we know external events directly by means of the organs, the nerves of which serve passively to support consciousness in the perception of such events. On the contrary, according to the opinion of most physiologists, the nerve fibers are active in the apprehension of external events, they modify it, alter it until it is well nigh unrecognizable, and turn it over to consciousness only after the original process has undergone still another trans- formation into new forms of mechanical energy in the ganglion cells of the outer brain. This is the difference between the physical theory of perception and the physiological.''
In this connection there are several more conditions pertaining to general sense-perception. First of all there is that so-called vicariousness of the senses which substitutes one sense for another, in representation. The *actual substitution of one sense by another as that of touch and sight, does not belong to the present discussion. The substitution of sound and sight is only apparent. E. g., when I have several times heard the half-noticed voice of some person without seeing him, I will imagine a definite face and appearance which *are pure imagination. So again, if I hear cries for help near some stream, I see more or less clearly the form of a drowning person, etc. It is quite different in touching and seeing; if I touch a ball, a die, a cat, a cloth, etc., with my eyes closed, then I may so clearly see the color of the object before me that I might be really seeing it. But in this case there is a real substitution of greater or lesser degree.
The same vicariousness occurs when perception is attributed to one sense while it properly belongs to another. This happens particularly at such times when one has not been present during the event or when the perception was made while only half awake, or a long time ago, and finally, when a group of other impressions have accompanied the event, so that there was not time enough, if I may say so, properly to register the sense impression. So, e. g., some person, especially a close friend, may have been merely heard and later quite convincingly supposed to have been seen. Sensitive people, who generally have an acuter olfactory sense than others, attach to any perceived odor all the other appropriate phenomena. The vicariousnesses of visual sensations are the most numerous and the most important. Anybody who has been pushed or beaten, and has felt the blows, will, if other circumstances permit and the impulse is strong enough, be convinced that he has seen his assaulter and the manner of the assault. Sometimes people who are shot at will claim to have seen the flight of the ball. And so again they will have seen in a dark night a comparatively distant wagon, although they have only heard the noise it made and felt the vibration. It is fortunate that, as a rule, such people try to be just in answering to questions which concern this substitution of one sense-perception for another. And such questions ought to be urgently put. That a false testimony can cause significant errors is as obvious as the fact that such substitutions are most frequent with nervous and imaginative persons.
Still more significant is that characteristic phenomenon, to us of considerable importance, which might be called retrospective illumination of perception. It consists in the appearance of a sense- perception under conditions of some noticeable interruption, when the stimulus does not, as a rule, give rise to that perception. I cite a simple example in which I first observed this fact. Since I was a child there had been in my bed-room a clock, the loud ticking of which habit of many years prevented my hearing. Once, as I lay awake in bed, I heard it tick suddenly three times, then fall silent and stop. The occurrence interested me, I quickly got a light and examined the clock closely. The pendulum still swung, but without a sound; the time was right. I inferred that the clock must have stopped going just a few minutes before. And I soon found out why: the clock is not encased and the weight of the pendulum hangs free. Now under the clock there always stood a chair which this time had been so placed as to be inclined further backward. The weight followed that inclination and so the silence came about.
I immediately made an experiment. I set the clock going again, and again held the weight back. The last beats of the pendulum were neither quicker nor slower, nor louder or softer than any others, before the sudden stoppage of the clock. I believe the explanation to be as follows: As customary noises especially are unheard, I did not hear the pendulum of the clock. But its sudden stopping disturbed the balance of sound which had been dominating the room. This called attention to the cause of the disturbance, i. e., the ticking which had ceased, and hence perception was intensified *backwards and I heard the last ticks, which I had not perceived before, one after another. The latent stimulus caused by the ticking worked backward. My attention was naturally awakened only *after the last tick, but my perception was consecutive.
I soon heard of another case, this time, in court. There was a shooting in some house and an old peasant woman, who was busy sewing in the room, asserted that she had just before the shooting heard a *few steps in the direction from which the shot must have come. Nobody would agree that there was any reason for supposing that the person in question should have made his final steps more noisily than his preceding ones. But I am convinced that the witness told the truth. The steps of the new arrival were perceived subconsciously; the further disturbance of the perception hindered her occupation and finally, when she was frightened by the shot, the upper levels of consciousness were illuminated and the noises which had already reached the subconsciousness passed over the threshold and were consciously perceived.
I learned from an especially significant case, how the same thing could happen with regard to vision. A child was run over and killed by a careless coachman. A pensioned officer saw this through the window. His description was quite characteristic. It was the anniversary of a certain battle. The old gentleman, who stood by the window thinking about it and about his long dead comrades, was looking blankly out into the street. The horrible cry of the unhappy child woke him up and he really began to see. Then he observed that he had in truth seen everything that had happened *before the child was knocked over—i. e., for some reason the coachman had turned around, turning the horses in such a way at the same time that the latter jumped sidewise upon the frightened child, and hence the accident. The general expressed himself correctly in this fashion: "I saw it all, but I did not perceive and know that I saw it until *after the scream of the child.'' He offered also in proof of the correctness of his testimony, that he, an old cavalry officer, would have had to see the approaching misfortune if he had consciously seen the moving of the coachman, and then he would have had to be frightened. But he knew definitely that he was frightened only when the child cried out—he could not, therefore, have consciously perceived the preceding event. His story was confirmed by other witnesses.
This psychological process is of significance in criminal trials, inasmuch as many actionable cases depend upon sudden and unexpected events, where retrospective illumination may frequently come in. In such cases it is most important to determine what actually has been perceived, and it is never indifferent whether we take the testimony in question as true or not.
With regard to the senses of criminals, Lombroso and Ottolenghi have asserted that they are duller than those of ordinary people. The assertion is based on a collection made by Lombroso of instances of the great indifference of criminals to pain. But he has overlooked the fact that the reason is quite another thing. Barbarous living and barbarous morals are especially dulling, so that indifference to pain is a characteristic of all barbarous nations and characters. Inasmuch as there are many criminals among barbarous people, barbarity, criminality and indifference to pain come together in a large number of cases. But there is nothing remarkable in this, and a direct relation between crime and dullness of the senses can not be demonstrated.
(b) The Sense of Sight.
Section 37. (I) General Considerations.
Just as the sense of sight is the most dignified of all our senses, it is also the most important in the criminal court, for most witnesses testify as to what they have seen. If we compare sight with the hearing, which is next in the order of importance, we discover the well-known fact that what is seen is much more certain and trustworthy than what is heard. "It is better to see once than to hear ten times,'' says the universally-valid old maxim. No exposition, no description, no complication which the data of other senses offer, can present half as much as even a fleeting glance. Hence too, no sense can offer us such surprises as the sense of sight. If I imagine the thunder of Niagara, the voice of Lucca, the explosion of a thousand cartridges, etc., or anything else that I have not heard, my imagination is certainly incorrect, but it will differ from reality only in degree. It is quite different with visual imagination. We need not adduce examples of magnificence like the appearance of the pyramids, a tropical light; of a famous work of art, a storm at sea, etc. The most insignificant thing ever seen but variously pictured in imagination will be greeted at first sight with the words: "But I imagined it quite different!'' Hence the tremendous importance of every local and material characteristic which the criminal court deals with. Every one of us knows how differently he has, as a rule, imagined the place of the crime to be; how difficult it is to arrive at an understanding with the witness concerning some unseen, local characteristic, and how many mistakes false images of the unseen have caused. Whenever I ciceroned anybody through the Graz Criminal Museum, I was continually assailed with "Does this or that look so? But I thought it looked quite different!'' And the things which evoke these exclamations are such as the astonished visitors have spoken and written about hundreds of times and often passed judgments upon. The same situation occurs when witnesses narrate some observation. When the question involves the sense of hearing some misunderstanding may be popularly assumed. But the people know little of optical illusions and false visual perceptions, though they are aware that incorrect auditions are frequent matters of fact. Moreover, to the heard object a large number of more or less certain precautionary judgments are attached. If anybody, e. g., has *heard a shot, stealthy footsteps, crackling flames, we take his experience always to be *approximate. We do not do so when he assures us he has *seen these things or their causes. Then we take them—barring certain mistakes in observation,—to be indubitable perceptions in which misunderstanding is impossible.
In this, again, is the basis for the distrust with which we meet testimony concerning hearsay. For we feel uncertain in the mere absence of the person whose conversation is reported, since his value can not be determined. But a part of the mistrust lies in the fact that it is not vision but the perennially half-doubted hearing that is in issue. Lies are assigned mainly to words; but there are lies which are visual (deceptions, maskings, illusions, etc.). Visual lies are, however, a diminishing minority in comparison with the lies that are heard.
The certainty of the correctness of vision lies in its being tested with the sense of touch,—i. e. in the adaptation of our bodily sense to otherwise existing things. As Helmholtz says, "The agreement between our visual perceptions and the external world, rests, at least in the most important matters, on the same ground that all our knowledge of the actual world rests on, upon the experience and the lasting test of their correctness by means of experiments, i. e., of the movements of our bodies.'' This would almost make it seem that the supreme judge among the senses is the touch. But that is not intended; we know well enough to what illusions we are subject if we trust the sense of touch alone. At the same time we must suppose that the question here is one of the nature of the body, and this can be measured only by something similar, i.e., by our own physical characteristics, but always under the control of some other sense, especially the sense of sight.
The visual process itself consists, according to Fischer, "of a compounded series of results which succeed each other with extraordinary rapidity and are causally related. In this series the following elements may principally be distinguished.
(1) The physico-chemical process.
(2) The physiologico-sensory.
(3) The psychological.
(4) The physiologico-motor.
(5) The process of perception.''
It is not our task to examine the first four elements. In order
clearly to understand the variety of perception, we have to deal with the last only. I once tried to explain this by means of the phenomenon of instantaneous photographs (cinematographs). If we examine one such representing an instant in some quick movement, we will assert that we never could have perceived it in the movement itself. This indicates that our vision is slower than that of the photographic apparatus, and hence, that we do not apprehend the smallest particular conditions, but that we each time unconsciously compound a group of the smallest conditions and construct in that way the so-called instantaneous impressions. If we are to compound a great series of instantaneous impressions in one galloping step, we must have condensed and compounded a number of them in order to get the image that we see with our eyes as instantaneous. We may therefore say that the least instantaneous image we ever see with our eyes contains many parts which only the photographic apparatus can grasp. Suppose we call these particular instances a, b, c, d, e, f, g, h, i, j, k, l, m; it is self-evident that the manner of their composition must vary with each individual. One man may compound his elements in groups of three: a, b, c,—d, e, f,—g, h, i, etc.; another may proceed in dyads: a, b,—c, d,—e, f,—g, h,—etc.; a third may have seen an unobservable instant later, but constructs his image like the first man: b, c, d,—l, m, n, etc.; a fourth works slowly and rather inaccurately, getting: a, c, d,—f, h, i,—etc. Such variations multiply, and when various observers of the same event describe it they do it according to their different characteristics. And the differences may be tremendous. Substitute numerals for letters and the thing becomes clear. The relative slowness of our apprehension of visual elements has the other consequence that we interpolate objects in the lacun of vision *according to our expectations. The best example of this sort of thing would be the perception of assault and battery. When ten people in an inn see how A raises a beer glass against B's head, five expect: "Now he'll pound him,'' and five others: "Now he'll throw it.'' If the glass has reached B's head none of the ten observers have seen how it reached there, but the first five take their oath that A pounded B with the glass, and the other five that he threw it at B's head. And all ten have really seen it, so firmly are they convinced of the correctness of their swift judgment of expectation. Now, before we treat the witness to some reproach like untruth, inattention, silliness, or something equally nice, *we had better consider whether his story is not true, and whether the difficulty might not really lie in the imperfection of our own sensory processes. This involves partly what Liebmann has called "anthropocentric vision,'' i. e., seeing with man as the center of things. Liebmann further asserts, "that we see things only in perspective sizes, i. e., only from an angle of vision varying with their approach, withdrawal and change of position, but in no sense as definite cubical, linear, or surface sizes. The apparent size of an object we call an angle of vision at a certain distance. But, what indeed is the different, true size? We know only relations of magnitude.'' This description is important when we are dealing with testimony concerning size. It seems obvious that each witness who speaks of size is to be asked whence he had observed it, but at the same time a great many unexpected errors occur, especially when what is involved is the determination of the size of an object in the same plane. One need only to recall the meeting of railway tracks, streets, alleys, etc., and to remember how different in size, according to the point of view of the witness, various objects in such places must appear. Everybody knows that distant things seem smaller than near ones, but almost nobody knows what the difference amounts to. For examples see Lotze, "Medical Psychology,'' Leipzig, 1852.