To know whether anything is natural law or not always depends upon the grade and standing of our immediate experience—and hence we shall never be able honestly to make any universal proposition. The only thing possible is the greatest possible accurate observation of probability in all known possible cases, and of the probability of the discovery of exceptions. Bacon called the establishment of reliable assumptions, counting up without meeting any contradictory case. But what gives us the law is the manner of counting. The untrained mind accepts facts as they occur without taking the trouble to seek others; the trained mind seeks the facts he needs for the premises of his inference. As Mill says, whatever has shown itself to be true without exception may be held universal so long as no doubtful exception is presented, and when the case is of such a nature that a real exception could not escape our observation.

This indicates how we are to interpret information given by others. We hear, “Inasmuch as this is always so it may be assumed to be so in the present case.” Immediate acceptance of this proposition would be as foolhardy as doubt in the face of all the facts. The proper procedure is to examine and establish the determining conditions, i.e., who has counted up this “always,” and what caution was used to avoid the overlooking of any exception. The real work of interpretation lies in such testing. We do not want to reach the truth with one blow, we aim only to approach it. But the step must be taken and we must know how large it is to be, and know how much closer it has brought us to the truth. And this is learned only through knowing who made the step and how it was made. Goethe’s immortal statement, “Man was not born to solve the riddle of the universe, but to seek out what the problem leads to in order to keep himself within the limits of the conceivable,” is valid for us too.

Our great mistake in examining and judging often lies in our setting too much value upon individual circumstances, and trying to solve the problem with those alone, or in not daring to use any given circumstance sufficiently. The latter represents that stupidity which is of use to scientific spirits when they lack complete proof of their points, but is dangerous in practical affairs. As a rule, it is also the consequence of the failure to evaluate what is given, simply because one forgets or is too lazy to do so. Proper action in this regard is especially necessary where certain legal proceedings have to occur which are entitled to a definite degree of probability without requiring certainty, i.e., preliminary examinations, arrests, investigations of the premises, etc. No law says how much probability is in such cases required. To say how much is impossible, but it is not unwise to stick to the notion that the event must appear true, if not be proved true, i.e., nothing must be present to destroy the appearance of truth. As Hume says, “Whenever we have reason to trust earlier experiences and to take them as standards of judgment of future experiences, these reasons may have probability.”

The place of probability in the positive determination of the order of modern criminal procedure is not insignificant. When the law determines upon a definite number of jurymen or judges, it is probable that this number is sufficient for the discovery of the truth. The system of prosecution establishes as a probability that the accused is the criminal. The idea of time-lapse assumes the probability that after the passage of a certain time punishment becomes illusory, and prosecution uncertain and difficult. The institution of experts depends on the probability that the latter make no mistakes. The warrant for arrest depends on the probability that the accused behaved suspiciously or spoke of his crime, etc. The oath of the witness depends on the probability that the witness will be more likely to tell the truth under oath, etc.

Modern criminal procedure involves not only probabilities but also various types of possibility. Every appeal has for its foundation the possibility of an incorrect judgment; the exclusion of certain court officials is based on the possibility of prejudice, or at least on the suspicion of prejudice; the publicity of the trial is meant to prevent the possibility of incorrectness; the revision of a trial depends on the possibility that even legal sentences may be false, and the institution of the defendant lawyer depends upon the possibility that a person without defense may receive injustice. All the formalities of the action of the court assume the possibility that without them improprieties may occur, and the institution of seizing letters and messages for evidence, asserts only the possibility that the latter contain things of importance, etc.

When the positive dicta of the law deal with possibility and probability in questions of great importance the latter become especially significant.

We have yet to ask what is meant by “rule” and what its relation is to probability. Scientifically “rule” means law subjectively taken and is of equal significance with the guiding line for one’s own conduct, whence it follows that there are only rules of art and morality, but no rules of nature. Usage does not imply this interpretation. We say that as a rule it hails only in the daytime; by way of exception, in the night also; the rule for the appearance of whales indicates that they live in the Arctic Ocean; a general rule indicates that bodies that are especially soluble in water should dissolve more easily in warm than in cold water, but salt dissolves equally well in both. Again we say: As a rule the murderer is an unpunished criminal; it is a rule that the brawler is no thief and vice versa; the gambler is as a rule a man of parts, etc. We may say therefore, that regularity is equivalent to customary recurrence and that whatever serves as rule may be expected as probable. If, i.e., it be said, that this or that happens as a rule, we may suppose that it will repeat itself this time. It is not permissible to expect more, but it frequently happens that we mistake rules permitting exceptions for natural laws permitting none. This occurs frequently when we have lost ourselves in the regular occurrences for which we are ourselves responsible and suppose that because things have been seen a dozen times they must always appear in the same way. It happens especially often when we have heard some phenomenon described in other sciences as frequent and regular and then consider it to be a law of nature. In the latter case we have probably not heard the whole story, nor heard general validity assigned to it. Or again, the whole matter has long since altered. Lotze wrote almost half a century ago, that he had some time before made the statistical observation that the great positive discoveries of exact physiology have an average life of about four years. This noteworthy statement indicates that great positive discoveries are set up as natural laws only to show themselves as at most regular phenomena which have no right to general validity. And what is true of physiology is true of many other sciences, even of the great discoveries of medicine, even legal medicine. This, therefore, should warn against too much confidence in things that are called “rules.” False usage and comfortable dependence upon a rule have very frequently led us too far. Its unreliability is shown by such maxims as “Three misses make a rule” or “Many stupidities taken together give a golden rule of life,” or “To-day’s exception is to-morrow’s rule,” or the classical perversion: “The rule that there are no rules without exception is a rule without exception, hence, there is one rule without exception.”

The unreliability of rules is further explained by their rise from generalization. We must not generalize, as Schiel says, until we have shown that if there are cases which contradict our generalizations we know those contradictions. In practice approximate generalizations are often our only guides. Natural law is too much conditioned, cases of it too much involved, distinctions between them too hard to make, to allow us to determine the existence of a natural phenomenon in terms of its natural characteristics as a part of the business of our daily life. Our own age generalizes altogether too much, observes too little, and abstracts too rapidly. Events come quickly, examples appear in masses, and if they are similar they tend to be generalized, to develop into a rule, while the exceptions which are infinitely more important are unobserved, and the rule, once made, leads to innumerable mistakes.

Section 29. (g) Chance.

The psychological significance of what we call chance depends upon the concept of chance and the degree of influence that we allow it to possess in our thinking. What is generally called chance, and what is called chance in particular cases, will depend to a significant degree upon the nature of the case. In progressive sciences the laws increase and the chance-happenings decrease; the latter indeed are valid only in particular cases of the daily life and in the general business of it. We speak of chance or accident when events cross which are determined in themselves by necessary law, but the law of the crossing of which is unknown. If, e.g., it is observed that where there is much snow the animals are white, the event must not be attributed to accident, for the formation of snow in high mountains or in the north, and its long stay on the surface of the earth develop according to special natural laws, and the colors of animals do so no less—but that these two orderly series of facts should meet requires a third law, or still better, a third group of laws, which though unknown some time ago, are now known to every educated person.