If this is really accomplished and some positive fact is established in the self-accusation, the question becomes one of finding the value seen by the confessor in blaming himself together with his fellow. Revenge, hatred, jealousy, envy, anger, suspicion, and other pa.s.sions will be the forces in which this value will be found. One man brings his ancient comrade into jeopardy in revenge for the latter's injustice in the division of the booty, or in deliberate anger at the commission of some dangerous stupidity in a burglary. Again, it often happens that he or she, through jealousy, accuses her or him in order that the other may be also imprisoned, and so not become disloyal. Business jealousy, again, is as influential as the attempt to prevent another from disposing of some hidden booty, or from carrying out by himself some robbery planned in partnership. These motives are not always easy to discover but are conceivable. There are also cases, not at all rare, in which the ordinary man is fully lacking in comprehension of "the subst.i.tute value," which makes him confess the complicity of his fellow. I am going to offer just one example, and inasmuch as the persons concerned are long since dead, will, by way of exception, mention their names and the improbability of their stories. In 1879 an old man, Blasius Kern, was found one morning completely snowed over and with a serious wound in the head. There was no possible suspicion of robbery as motive of the murder, inasmuch as the man was on his way home drunk, as usual, and it was supposed that he had fallen down and had smashed his skull. In 1881 a young fellow, Peter Seyfried, came to court and announced that he had been hired by Blasius Kern's daughter, Julia Hauck, and her husband August Hauck, to kill the old fellow, who had become unendurable through his love of drink and his endless quarrelsomeness; and accordingly he had done the deed. He had been promised an old pair of trousers and three gulden, but they had given him the trousers, not the money, and as all his attempts to collect payment had failed he divulged the secret of the Hauck people. When I asked him if he were unaware that he himself was subject to the law he said, "I don't care; the others at least will also be punished;-why haven't they kept their word." And this lad was very stupid and microcephalic, but according to medico- legal opinion, capable of distinguishing between right and wrong. His statements proved themselves true to the very last point.

So significantly weak as this in fundamental reliability, very few confessions will appear to be, but the reasons for confessions, difficult both to find and to judge, are many indeed. The only way to attain certainty is through complete and thorough-going knowledge of all the external conditions, but primarily through sound psychological insight into the nature of both the confessor and those he accuses. Evidently the first is by far the more important: what he is beneath the surface, his capacities, pa.s.sions, intentions, and purposes, must all be settled if any decision is to be arrived at as to the advantage accruing to a man by the accusation of others. For example, the pa.s.sionate character of some persons may indicate beyond a doubt that they might find pleasure in suffering provided they could cause suffering to others at that price. Pa.s.sion is almost always what impels men, and what pa.s.sion in particular lies behind a confession will be revealed partly by the crime, partly by the relation of the criminals one to the other, partly by the personality of the new victim. If this pa.s.sion was strong enough to deal, if I may use the term, anti-egoistically, it can be discovered only through the study of its possessor. It may be presupposed that everybody acts according to his own advantage-the question asks merely what this advantage is in the concrete, and whether he who seeks it, seeks it prudently. Even the satisfaction of revenge may be felt as an advantage if it is more pleasurable than the pain which follows confession-the matter is one of relative weight and is prudently sought as the subst.i.tution of an immediate and petty advantage for a later and greater one.

Another series of procedures is of importance in determining proof, where circ.u.mstances are denied which have no essential relation to the crime. They bring the presentation of proof into a bypath so that the essential problem of evidence is left behind. Then if the denied circ.u.mstance is established as a fact it is falsely supposed that the guilt is so established. And in this direction many mistakes are frequently made. There are two suggestive examples. Some years ago there lived in Vienna a very pretty bachelor girl, a sales-person in a very respectable shop. One day she was found dead in her room. Inasmuch as the judicial investigation showed acute a.r.s.enic poisoning, and as a tumbler half full of sweetened water and a considerable quant.i.ty of finely powdered a.r.s.enic was found on her table, these two conditions were naturally correlated. From the neighbors it was learned that the dead girl had for some time been intimate with an unknown gentleman who visited her

frequently, but whose presence was kept as secret as possible by both. This gentleman, it was said, had called on the girl on the evening before her death. The police inferred that the man was a very rich merchant, residing in a rather distant region, who lived peaceably with his much older wife and therefore kept his illicit relations with the girl secret. It was further established at the autopsy that the girl was pregnant, and so the theory was formed that the merchant had poisoned his mistress and in the examination this deed was set down against him. Now, if the man had immediately confessed that he knew the dead girl, and stood in intimate relation with her and that he had called on her the last evening; if he had a.s.serted perhaps that she was in despair about her condition, had quarreled with him and had spoken of suicide, etc., then suicide would unconditionally have had to be the verdict. In any event, he never could have been accused, inasmuch as there was no additional evidence of poisoning. But the man conceived the unfortunate notion of denying that he knew the dead girl or had any relations with her, or that he had ever, even on that last evening, called on her. He did this clearly because he did not want to confess a culpable relation to public opinion, especially to his wife. And the whole question turned upon this denied circ.u.mstance. The problem of evidence was no longer, "Has he killed her," but "Did he carry on an intimacy with her." Then it was proved beyond reasonable doubt through a long series of witnesses that his visits to the girl were frequent, that he had been there on the evening before her death, and that there could be no possible doubt as to his ident.i.ty. That settled his fate and he was sentenced to death. If we consider the case psychologically we have to grant that his denial of having been present might have for motive as much the fact that he had poisoned the girl, as that he did not want to admit the relation at the beginning. Later on, when he completely understood the seriousness of his situation, he thought a change of front too daring and hoped to get on better by sticking to his story. Now, as we have seen, what was proved was the fact that he knew and visited the girl; what he was sentenced for was the murder of the girl.

A similar case, particularly instructive in its development, and especially interesting because of the significant study (of the suggestibility of witnesses) of Dr. Von Schrenck-Notzing and Prof. Grashey, kept the whole of Munich in excitement some years ago. A widow, her grown-up daughter, and an old servant were stifled

and robbed in their home. The suspicion of the crime fell upon a brick-layer who had once before made a confession concerning another murder and of whom it was known that some time before the deed was done he had been building a closet into the house of the three murdered women. Through various combinations of the facts the supposition was reached that the mason got entry into the house on the pretense of examining whether or not the work he had done on the closet had caused any damage, and had then committed the thieving murder. Now here again, if the mason had said: "Yes, I was without a job, wanted to get work, entered the house under the a.s.signed pretense, and appeared to see about the closet and had myself paid for the apparently repaired improvement, left the three women unharmed, and they must only after that have been killed,"-if he had said this, his condemnation would have been impossible, for all the other testimony was of subordinate importance. Now suppose the man was innocent, what could he have thought: "I have already been examined once in a murder case, I found myself in financial difficulties, I still am in such difficulties-if I admit that I was at the place of the crime at the time the crime was committed, I will get into serious trouble, which I won't, if I deny my presence." So he really denied having been in the house or in the street for some time, and inasmuch as this was shown by many witnesses to be untrue, his presence at the place where the crime was committed was identified with the unproved fact that he had committed it, and he was condemned.

I do not a.s.sert that either one or the other of these persons was condemned guiltlessly, or that such "side issues" have no value and ought not to be proved. I merely point out that caution is necessary in two directions. First of all, these side issues must not be identified with the central issue. Their demonstration is only preparatory work, the value of which must be established cautiously and without prejudice. It may be said that the feeling of satisfaction with what has been done causes jurists frequently to forget what must yet be done, or to undervalue it. Further, a psychological examination must seek out the motives which led or might have led the accused to deny some point not particularly dangerous to him. In most cases an intelligible ground for such action can be discovered, and if the psychologically prior conditions are conceived with sufficient narrowness to keep us from a.s.suming unconditional guilt, we are at least called upon to be careful.

This curious danger of identification of different issues as the aim of presentation of evidence, occurs much more frequently and with comparatively greater degree in the cases of individual witnesses who are convinced of the princ.i.p.al issue when a side issue is proved. Suppose a witness is called on to identify a man as somebody who had stabbed him in a serious a.s.sault, and that he has also to explain whether the quarrel he had had with this man a short time ago was of importance. If the suspect is desirous of having the quarrel appear as harmless, and the wounded person a.s.serts that the quarrel was serious, the latter will be convinced, the moment his contention may be viewed as true, that his opponent was really the person who had stabbed him. There is, of course, a certain logical justification for this supposition, but the psychological difficulty with it is the fact that this case, like many others, involves the identification of what is inferred with what is perceived. It is for this reason that the mere fact of arrest is to most people a conviction of guilt. The witness who had first identified A as only the probable criminal becomes absolutely convinced of it when A is presented to him in stripes, even though he knows that A has been arrested on his own testimony alone. The appearance and the surroundings of the prisoner influence many, and not merely uneducated people, against the prisoner, and they think, involuntarily, "If he were not the one, they would not have him here."

Section 24. (b) Causation.[1]

If we understand by the term cause the axiom that every change has an occasion, hence that every event is bound up with a number of conditions which when lacking in whole or in part would prevent the appearance of the event, while their presence would compel its appearance, then the whole business of the criminalist is the study of causes. He must indeed study not only whether and how crime and criminal are causally related, but also how their individual elements are bound to each other and to the criminal; and finally, what causation in the criminal, considered with regard to his individual characteristics, inevitably led to the commission of the crime. The fact that we deal with the problem of cause brings us close to other sciences which have the same task in their own re-

[1] Max Mayer: Der Kausalzusammenhang zwischen Handlung und Erfolg in Strafrecht. 1899.

von Rohland. Die Kausallehre im Strafreeht. Leipzig 1903 H. Gross's Archiv, XV, 191.

searches; and this is one of the reasons for the criminalist's necessary concern with other disciplines. Of course no earnest criminalist can pursue other studies for their own sane, he has no time; but he must look about him and study the methods used in other sciences. In the other sciences we learn method, but not as method, and that is all that we need. And we observe that the whole problem of method is grounded on causation. Whether empirically or aprioristically does not matter. We are concerned solely with causation.

In certain directions our task is next to the historians' who aim to bring men and events into definite causal sequence. The causal law is indubitably the ideal and only instructive instrument in the task of writing convincing history, and it is likewise without question that the same method is specifically required in the presentation of evidence. Thus: "This is the causal chain of which the last link is the crime committed by A. Now I present the fact of the crime and include only those events which may be exclusively bound up with A's criminality-and the crime appears as committed. Now again, I present the fact of the crime and exclude all those events which can without exception be included only if A is not a criminal- and there is no crime."[1]

Evidently the finding of causes involves, according to the complexities of the case, a varying number of subordinate tasks which have to be accomplished for each particular incident, inasmuch as each suspicion, each statement pro or con has to be tested. The job is a big one but it is the only way to absolute and certain success, provided there is no mistake in the work of correlating events. As Sch.e.l.l says: "Of all the observed ident.i.ties of effect in natural phenomena only one has the complete strength of mathematical law-the general law of causation. The fact that everything that has a beginning has a cause is as old as human experience." The application of this proposition to our own problem shows that we are not to turn the issue in any unnecessary direction, once we are convinced that every phenomenon has its occasion. We are, on the contrary, to demonstrate this occasion and to bring it into connection with every problem set by the testimony at any moment. In most cases the task, though not rigidly divided, is double and its quality depends upon the question whether the criminal was known from the beginning or not. The duality is foremost, and lasts

[1] Cf. S. Strieker: Studien ber die a.s.soziation der Vorstellungen. Vienna 1883. longest if only the deed itself is known, and if the judge must limit himself entirely to its sole study in order to derive from it its objective situation.The greatest mistakes in a trial occur when this derivation of the objective situation of the crime is made unintelligently, hastily or carelessly, and conversely the greatest successes are due to its correct rendering. But such a correct rendering is no more than the thoroughgoing use of the principle of causality. Suppose a great crime has been committed and the personality of the criminal is not revealed by the character of the crime. The mistake regularly made in such a case is the immediate and superficial search for the personality of the criminal instead of what should properly proceed-the study of the causal conditions of the crime. For the causal law does not say that everything which occurs, taken as a whole and in its elements, has one ground-that would be simply categorical emptiness. What is really required is an efficient and satisfying cause. And this is required not merely for the deed as a whole but for every single detail. When causes are found for all of these they must be brought together and correlated with the crime as described, and then integrated with the whole series of events.The second part of the work turns upon the suspicion of a definite person when his own activity is interpolated as a cause of the crime. Under some conditions again, the effect of the crime on the criminal has to be examined, i. e., enrichment, deformation, emotional state, etc. But the evidence of guilt is established only when the crime is accurately and explicitly described as the inevitable result of the activity of the criminal and his activity only. This systematic work of observing and correlating every instant of the supposed activities of the accused (once the situation of the crime is defined as certainly as possible), is as instructive as it is promising of success. It is the one activity which brings us into touch with bare perception and its reproduction. "All inference with regard to facts appears to depend upon the relation of cause to effect; by virtue of this relation alone may we rely upon the evidence of our memories and our senses."[1] Hume ill.u.s.trates this remark with the following example: If a clock or some other machine is found on a desert island, the conclusion is drawn that men are or were on the island. The application is easy enough. The presence of a clock, the presence of a three-cornered wound is perceived by the senses-that men were there, that the wound was made with a specific kind of in- [1] Meinong: Humestudien. Vienna 1882. strument, is a causal inference. Simple as this proposition of Hume's is, it is of utmost importance in the law because of the permanent and continually renewed problems: What is the effect in *this case? What is the cause? Do they belong together? Remembering that these questions make our greatest tasks and putting them, even beyond the limit of disgust, will save us from grave errors.There is another important condition to which Hume calls attention and which is interpreted by his clever disciple Meinong. It is a fact that without the help of previous experience no causal nexus can be referred to an observation, nor can the presence of such be discovered in individual instances. It may be postulated only. A cause is essentially a complex in which every element is of identical value. And this circ.u.mstance is more complicated than it appears to be, inasmuch as it requires reflection to distinguish whether only one or more observations have been made. Strict self-control alone and accurate enumeration and supervision will lead to a correct decision as to whether one or ten observations have been made, or whether the notion of additional observations is not altogether illusory.This task involves a number of important circ.u.mstances. First of all must be considered the manner in which the man on the street conceives the causal relation between different objects. The notion of causality, as Schwarz[1] shows, is essentially foreign to the man on the street. He is led mainly by the a.n.a.logy of natural causality with that of human activity and pa.s.sivity, e. g., the fire is active with regard to water, which simply must sizzle pa.s.sively. This observation is indubitably correct and significant, but I think Schwarz wrong to have limited his description to ordinary people; it is true also of very complex natures. It is conceivable that external phenomena shall be judged in a.n.a.logy with the self, and inasmuch as the latter often appears to be purely active, it is also supposed that those natural phenomena which appear to be especially active are really so.In addition, many objects in the external world with which we have a good deal to do, and are hence important, do as a matter of fact really appear to be active-the sun, light, warmth, cold, the weather, etc., so that we a.s.sign activity and pa.s.sivity only according to the values the objects have for us. The ensuing mistake is the fact that we overlook the alternations between activity and pas- [1] Das Wahrnehmungsproblem von Standpunkte des Physikers, Physiologen und Philosophen. Leipzig 1892. sivity, or simply do not make the study such alternations require; yet the correct apportionment of action and reaction is, for us, of greatest importance. In this regard, moreover, there is always the empty problem as to whether two things may stand in causal relation,- empty, because the answer is always yes. The scientific and practical problem is as to whether there exists an actual causal nexus. The same relation occurs in the problem of reciprocal influences. No one will say, for example, that any event exercises a reciprocal influence on the sun, but apart from such relatively few cases it would not only be supposed that A is the cause of the effect B, but also that B might have reciprocally influenced A. Regard for this possibility may save one from many mistakes.One important source of error with regard to cause and effect lies in the general and profound supposition that the cause must have a certain similarity to the effect. So Ovid, according to J. S. Mill, has Medea brew a broth of long-lived animals; and popular superst.i.tions are full of such doctrine. The lung of a long-winded fox is used as a cure for asthma, the yarrow is used to cure jaundice, agaricos is used for blisters, aristolochia (the fruit of which has the form of a uterus) is used for the pains of child-birth, and nettle-tea for nettle-rash. This series may be voluntarily increased when related to the holy patron saints of the Catholic Church, who are chosen as protectors against some especial condition or some specific difficulty because they at one time had some connection with that particular matter. So the holy Odilia is the patron saint for diseases of the eye, not because she knew how to cure the eyes, but because her eyes were put out with needles. The thief Dismas is the patron of the dying because we know nothing about him save that he died with Christ. St. Barbara, who is pictured together with a tower in which she was imprisoned, and which was supposed to be a powder house, has become the patron saint of artillery. In the same manner St. Nicholas is, according to Simrock, the patron of sailors because his name resembles Nichus, Nicor, Nicker, which is the name of the unforgotten old German sea-deity.Against such combinations, external and unjustified, not even the most educated and skilful is safe. n.o.body will doubt that he is required to make considerable effort in his causal interpretation because of the sub-conscious influence of such similarities. The matter would not be so dangerous, all in all, because such mistakes may be easily corrected and the attention of people may be called to the inadequacy of such causation-but the reason for this kind of correlations is rarely discovered. Either people do not want to tell it because they instinctively perceive that their causal interpretation cannot be justified, or they cannot even express it because the causal relation had been a.s.sumed only subconsciously, and they are hence unaware of the reasons for it and all the more convinced that they are right. So for example, an intelligent man told me that he suspected another of a murder because the latter's mother died a violent death. The witness stuck to his statement: "the man who had once had something to do with killing must have had something to do with this killing." In a similar manner, a whole village accused a man of arson because he was born on the night on which a neighboring village burned down. Here, however, there was no additional argument in the belief that his mother had absorbed the influence of the fire inasmuch as the latter was told that there had been a fire only after the child was born. "He once had something to do with fire," was the basis of the judgment, also in this case.There are innumerable similar examples which, with a large number of habitual superst.i.tious presuppositions, make only false causality. Pearls mean tears because they have similar form; inasmuch as the cuckoo may not without a purpose have only two calls at one time and ten or twenty at another, the calls must mean the number of years before death, before marriage, or of a certain amount of money, or any other countable thing. Such notions are so firmly rooted in the peasantry and in all of us, that they come to the surface, whether consciously or unconsciously, and influence us more than we are accustomed to suppose they do. Whenever anybody a.s.sures us that he is able to a.s.sert absolutely, though not altogether prove a thing, this a.s.surance may be variously grounded, but not rarely it is no more than one of these false correlations. Schopenhauer has said, that "motivation is causality seen from within,"-and one may add conversely that causality is motivation seen from without. What is a.s.serted must be motivated, and that is done by means of causality-if no real ultimate cause is found a false, superficial and insufficient one is adopted, inasmuch as we ever strive to relate things causally, in the knowledge that, otherwise, the world would be topsy-turvy. "Everywhere," says Stricker, "we learn that men who do not a.s.sociate their experiences according to right cause are badly adapted to their environment; the pictures of artists are disliked, the laborer's work does not succeed; the tradesman loses his money, and the general his battle. And we may add, "The criminalist his case." For whoever seeks the reason for a lost case certainly will find it in the ignorance of the real fact and in the incorrect cordination of cause and effect. The most difficult thing in such cordination is not that it has to be tested according to the notion one has for himself of the chain of events; the difficulty lies in the fact that the point of view and mental habits of the man who is suspected of the effects must be adopted. Without this the causal relations as they are arrived at by the other can never be reached, or different results most likely ensue.The frequency of mistakes like those just mentioned is well known. They affect history. Even La Rochefoucauld was of the opinion that the great and splendid deeds which are presented by statesmen as the outcome of far-reaching plans are, as a rule, merely the result of inclination and pa.s.sion. This opinion concerns the lawyer's task also, for the lawyer is almost always trying to discover the moving, great, and unified plan of each crime, and in order to sustain such a notion, prefers to perfect a large and difficult theoretic construction, rather than to suppose that there never was a plan, but that the whole crime sprang from accident, inclination, and sudden impulse. The easiest victims in this respect are the most logical and systematic lawyers; they merely presuppose, "I would not have done this" and forget that the criminal was not at all so logical and systematic, that he did not even work according to plan, but simply followed straying impulses.Moreover, a man may have determined his causal connections correctly, yet have omitted many things, or finally have made a voluntary stop at some point in his work, or may have carried the causal chain unnecessarily far. This possibility has been made especially clear by J. S. Mill, who showed that the immediately preceding condition is never taken as cause. When we throw a stone into the water we call the cause of its sinking its gravity, and not the fact that it has been thrown into the water. So again, when a man falls down stairs and breaks his foot, in the story of the fall the law of gravity is not mentioned; it is taken for granted. When the matter is not so clear as in the preceding examples, such facts are often the cause of important misunderstandings. In the first case, where the immediately preceding condition is *not mentioned, it is the inaccuracy of the expression that is at fault, for we see that at least in scientific form, the efficient cause is always the immedi- ately preceding condition. So the physician says, "The cause of death was congestion of the brain in consequence of pressure resulting from extravasation of the blood." And he indicates only in the second line that the latter event resulted from a blow on the head. In a similar manner the physicist says that the board was sprung as a consequence of the uneven tension of the fibers; he adds only later that this resulted from the warmth, which again is the consequence of the direct sunlight that fell on the board. Now the layman had in both cases omitted the proximate causes and would have said in case 1, "The man died because he was beaten on the head," and in case 2 "The board was sprung because it lay in the sun." We have, therefore, to agree to the surprising fact that the layman skips more intermediaries than the professional, but only because either he is ignorant of or ignores the intervening conditions. Hence, he is also in greater danger of making a mistake through omission.Inasmuch as the question deals only with the scarcity of correct knowledge of proximate causes, we shall set aside the fact that lawyers themselves make such mistakes, which may be avoided only by careful self-training and cautious attention to one's own thoughts. But we have at the same time to recognize how important the matter is when we receive long series of inferences from witnesses who give expression only to the first and the last deduction. If we do not then examine and investigate the intermediary links and their justification, we deserve to hear extravagant things, and what is worse, to make them, as we do, the foundation of further inference. And once this is done no man can discover where the mistake lies.If again an inference is omitted as self-evident (cf. the case of gravity, in falling down stairs) the source of error and the difficulty lies in the fact that, on the one hand, not everything is as self-evident as it seems; on the other, that two people rarely understand the same thing by "self-evident," so that what is self-evident to one is far from so to the other. This difference becomes especially clear when a lawyer examines professional people who can imagine offhand what is in no sense self-evident to persons in other walks of life. I might cite out of my own experience, that the physicist Boltzmann, one of the foremost of living mathematicians, was told once upon a time that his demonstrations were not sufficiently detailed to be intelligible to his cla.s.s of non-professionals, so that his hearers could not follow him. As a result, he carefully counted the simplest additions or interpolations on the blackboard, but at the same time integrated them, etc., in his head, a thing which very few people on earth can do. It was simply an off-hand matter for this genius to do that which ungenial mortals can not.This appears in a small way in every second criminal case. We have only to subst.i.tute the professionals who appear as witnesses. Suppose, e. g., that a hunter is giving testimony. He will omit to state a group of correlations; with regard to things which are involved in his trade, he will reach his conclusion with a single jump. Then we reach the fatal circle that the witness supposes that we can follow him and his deductions, and are able to call his attention to any significant error, while we, on the other hand, depend on his professional knowledge, and agree to his leaping inferences and allow his conclusions to pa.s.s as valid without knowing or being able to test them.The notion of "specialist" or "professional" must be applied in such instances not only to especial proficients in some particular trade, but also to such people as have by accident merely, any form of specialized knowledge, e. g., knowledge of the place in which some case had occurred. People with such knowledge present many a thing as self-evident that can not be so to people who do not possess the knowledge. Hence, peasants who are asked about some road in their own well known country reply that it is "straight ahead and impossible to miss" even when the road may turn ten times, right and left.Human estimates are reliable only when tested and reviewed at each instant; complicated deductions are so only when deduction after deduction has been tested, each in itself, Lawyers must, therefore, inevitably follow the rule of requiring explication of each step in an inference-such a requirement will at least narrow the limits of error.The task would be much easier if we were fortunate enough to be able to help ourselves with experiments. As Bernard[1] says, "There is an absolute determinism in the existential conditions of natural phenomena, as much in living as in non-living bodies. If the condition of any phenomenon is recognized and fulfilled the phenomenon must occur whenever the experimenter desires it." But such determination can be made by lawyers in rare cases only, and to-day the criminalist who can test experimentally the generally a.s.serted circ.u.mstance attested by witnesses, accused, or experts, [1] C. Bernard: Introduction cine Experimentale. Paris 1871. is a rarissima avis. In most cases we have to depend on our experience, which frequently leaves us in difficulties if we fail thoroughly to test it. Even the general law of causation, that every effect has its cause, is formulated, as Hume points out, only as a matter of habit. Hume's important discovery that we do not observe causality in the external world, demonstrates only the difficulty of the interpretation of causality. The weakness of his doctrine lies in his a.s.sertion that the knowledge of causality may be obtained through habit because we perceive the connection of similars, and the understanding, through habit, deduces the appearance of the one from that of the other. These a.s.sertions of the great thinker are certainly correct, but he did not know how to ground them. Hume teaches the following doctrine: The proposition that causes and effects are recognized, not by the understanding but because of experience, will be readily granted if we think of such things as we may recollect we were once altogether unacquainted with. Suppose we give a man who has no knowledge of physics two smooth marble plates. He will never discover that when laid one upon the other they are hard to separate. Here it is easily observed that such properties can be discovered only through experience. n.o.body, again, has the desire to deceive himself into believing that the force of burning powder or the attraction of a magnet could have been discovered a priori. But this truth does not seem to have the same validity with regard to such processes as we observed almost since breath began. With regard to them, it is supposed that the understanding, by its own activity, without the help of experience can discover causal connections. It is supposed that anybody who is suddenly sent into the world will be able at once to deduce that a billiard ball will pa.s.s its motion on to another by a push.But that this is impossible to derive a priori is shown through the fact that elasticity is not an externally recognizable quality, so that we may indeed say that perhaps no effect can be recognized unless it is experienced at least once. It can not be deduced a priori that contact with water makes one wet, or that an object responds to gravity when held in the hand, or that it is painful to keep a finger in the fire. These facts have first to be experienced either by ourselves or some other person. Every cause, Hume argues therefore, is different from its effect and hence can not be found in the latter, and every discovery or representation of it a priori must remain voluntary. All that the understanding can do is to simplify the fundamental causes of natural phenomena and to deduce the individual effects from a few general sources, and that, indeed, only with the aid of a.n.a.logy, experience, and observation.But then, what is meant by trusting the inference of another person, and what in the other person's narrative is free from inference? Such trust means, to be convinced that the other has made the correct a.n.a.logy, has made the right use of experience, and has observed events without prejudice. That is a great deal to presuppose, and whoever takes the trouble of examining however simple and short a statement of a witness with regard to a.n.a.logy, experience, and observation, must finally perceive with fear how blindly the witness has been trusted. Whoever believes in knowledge a priori will have an easy job: "The man has perceived it with his mind and reproduced it therewith; no objection may be raised to the soundness of his understanding; ergo, everything may be relied upon just as he has testified to it." But he who believes in the more uncomfortable, but at least more conscientious, skeptical doctrine, has, at the minimum, some fair reason for believing himself able to trust the intelligence of a witness. Yet he neither is spared the task of testing the correctness of the witness's a.n.a.logy, experience and observation.Apriorism and skepticism define the great difference in the att.i.tude toward the witness. Both skeptic and apriorist have to test the desire of the witness to lie, but only the skeptic needs to test the witness's ability to tell the truth and his possession of sufficient understanding to reproduce correctly; to examine closely his innumerable inferences from a.n.a.logy, experience and observation. That only the skeptic can be right everybody knows who has at all noticed how various people differ in regard to a.n.a.logies, how very different the experiences of a single man are, both in their observation and interpretation. To distinguish these differences clearly is the main task of our investigation.There are two conditions to consider. One is the strict difference between what is causally related and its accidental concomitants,- a difference with regard to which experience is so often misleading, for two phenomena may occur together at the same time without being causally connected. When a man is ninety years old and has observed, every week in his life, that in his part of the country there is invariably a rainfall every Tuesday, this observation is richly and often tested, yet n.o.body will get the notion of causally connecting Tuesday and rain-but only because such connection would be regarded as generally foolish. If the thing, however, may be attributed to coincidence with a little more difficulty, then it becomes easier to suppose a causal connection; e. g., as when it rains on All- souls day, or at the new moon. If the accidental nature of the connection is still less obvious, the observation becomes a much- trusted and energetically defended meteorological law. This happens in all possible fields, and not only our witnesses but we ourselves often find it very difficult to distinguish between causation and accident. The only useful rule to follow is to presuppose accident wherever it is not indubitably and from the first excluded, and carefully to examine the problem for whatever causal connection it may possibly reveal. "Whatever is united in any perception must be united according to a general rule, but a great deal more may be present without having any causal relation."The second important condition was mentioned by Schopenhauer:[1] "As soon as we have a.s.signed causal force to any great influence and thereby recognized that it is efficacious, then its intensification in the face of any resistance according to the intensity of the resistance will produce finally the appropriate effect. Whoever cannot be bribed by ten dollars, but vacillates, will be bribed by twenty-five or fifty."This simple example may be generalized into a golden rule for lawyers and requires them to test the effect of any force on the accused at an earlier time in the latter's life or in other cases,- i. e., the early life of the latter can never be studied with sufficient care. This study is of especial importance when the question is one of determining the culpability of the accused with regard to a certain crime. We have then to ask whether he had the motive in question, or whether the crime could have been of interest to him. In this investigation the problem of the necessary intensity of the influence in question need not, for the time, be considered; only its presence needs to be determined. That it may have disappeared without any demonstrable special reason is not supposable, for inclinations, qualities, and pa.s.sions are rarely lost; they need not become obvious so long as opportunity and stimulus are absent, and they may be in some degree suppressed, but they manifest themselves as soon as-Schopenhauer's twenty-five or fifty dollars appear. The problem is most difficult when it requires the conversion of certain related properties, e. g., when the problem is one of suspecting a person of murderous inclination, and all that [1] Schopenhauer: Die beiden Grundprobleme der Ethik. can be shown in his past life is the maltreatment of animals. Or again, when cruelty has to be shown and all that is established is great sensuality. Or when there is no doubt about cruelty and the problem is one of supposing intense avarice. These questions of conversion are not especially difficult, but when it must be explained to what such qualities as very exquisite egoism, declared envy, abnormal desire for honor, exaggerated conceit, and great idleness may lead to, the problem requires great caution and intensive study.Section 25. (c) Skepticism.Hume's skepticism is directly connected with the subject of the preceding chapter, but wants still a few words for itself. Though it is not the lawyer's problem to take an att.i.tude with regard to philosophical skepticism, his work becomes essentially easier through the study of Hume's doctrines.According to these, all we know and infer, in so far as it is unmathematical, results from experience, and our conviction of it and our reasoning about it, means by which we pa.s.s the bounds of sense-perception, depend on sensation, memory and inference from causation. Our knowledge of the relation of cause and effect results also from experience, and the doctrine, applied to the work of the criminalist, may be formulated as follows: "Whatever we take as true is not an intellectual deduction, but an empirical proposition." In other words, our presuppositions and inferential knowledge depend only upon those innumerable repet.i.tions of events from which we postulate that the event recurred in the place in question. This sets us the problem of determining whether the similar cases with which we compare the present one really are similar and if they are known in sufficiently large numbers to exclude everything else.Consider a simple example. Suppose somebody who had traveled all through Europe, but had never seen or heard of a negro, thought about the pigmentation of human beings: neither all his thinking nor the a.s.sistance of all possible scientific means can lead him to the conclusion that there are also black people-that fact he can only discover, not think out. If he depends only on experience, he must conclude from the millions of examples he has observed that all human beings are white. His mistake consists in the fact that the immense number of people he has seen belong to the inhabitants of a single zone, and that he has *failed to observe the inhabitants of other regions. In our own cases we need no examples, for I know of no inference which was not made in the following fashion: "The situation was so in a hundred cases, it must be so in this case." We rarely ask whether we know enough examples, whether they were the correct ones, and whether they were exhaustive. It will be no mistake to a.s.sert that we lawyers do this more or less consciously on the supposition that we have an immense collection of suggestive a priori inferences which the human understanding has brought together for thousands of years, and hence believe them to be indubitably certain. If we recognize that all these presuppositions are compounds of experience, and that every experience may finally show itself to be deceptive and false; if we recognize how the actual progress of human knowledge consists in the addition of one hundred new experiences to a thousand old ones, and if we recognize that many of the new ones contradict the old ones: if we recognize the consequence that there is no reason for the mathematical deduction from the first to the hundred-and-first case, we shall make fewer mistakes and do less harm. In this regard, Hume[1] is very illuminative.