incapable of explanation upon any other hypothesis than that of his guilt."1

"Circumstantial evidence, I need hardly tell you, is most delusive in its character. Analyzed, what do we find it to be? It has been truly argued that there is, and can be, no cause without an effect. In considering circumstantial evidence, the mind of the investigator is presented with the relation of a number of facts, or effects, and he is asked to deduce that they are all attributable to a stated cause. For example, a pedler is known to have started out upon a lonely road, and to have in his pack certain wares, a given amount of money in specified coins and bills, wearing a watch and chain, and he is subsequently found murdered, by the wayside. Later, a tramp is arrested upon whose person is found the exact missing money, and many of the articles which were known to have been in the pack. He is charged with the crime, and the evidence against him is circumstantial. His possession of these articles is an effect, which is said to be attributable to a cause, to wit, the killing of the pedler. But strong as such evidence may appear, as I have said, it is delusive. For just as the prosecution ask you to believe that a number of effects are traceable to a single cause, the crime charged, so also it is possible that all of the effects may have resulted from various causes. Thus in the case cited, the tramp may have been a thief, and may have stolen the articles from the pedler after some other person had killed him. And if it could be shown that the watch and chain were missing, and yet were not found upon the tramp, that would be as good evidence in his favor, as the other facts are against him. So that in circumstantial evidence the chain must be complete. If a single link be missing, or have a flaw, the argument is inconclusive, and a doubt is created, the benefit of which must invariably be given in favor of the accused." 2

The character of its contents has much to do with the credibility of evidence. What is probable on the 1 Judge Porter, Babcock Conspiracy Case.

2 Ottolengui, Modern Wizard, 170.

Improbable

face of it, what squares with ordinary human experience, what is consistent with other facts already known in the case, is readily accepted. and IncrediBut if evidence carries improbability on its ble Evidence. face, if it proposes strange, unusual, unaccountable or inconsistent circumstances, the thoughtful reasoner at once rejects it. The accounts in the Bible of Jonah's experience with the whale, of Joshua's causing the sun to stand still, of the raising of Lazarus, and of miracles in general, are questioned by many because these occurrences are so far removed from common experience. For the same reason the revelations to the latter-day saints find slow acceptance. On the other hand, Defoe's account of the plague, though fictitious, is still occasionally quoted as authentic, because of its "natural

The poet, Story, makes a Roman lawyer argue that Judas was "a rash and visionary man" rather than a base criminal, since it does not accord with human experience that one should sell his Lord for so small a sum, nor that a criminal should have been chosen to Judas's place among the twelve; nor that a criminal could have hidden his character so long; nor that he would have flung back the bribe, repenting of his act, when he had the approval of his race; nor that he should go at once and hang himself in horror of what he had done.

and Contra

Evidence, to be convincing, must be consistent in all its parts as well as with facts otherwise Inconsistent known. A witness injures his credibility dictory as soon as one part of his story fails to tally Testimony. with any other part. If one part contradicts another,

one or all must be rejected. Of two contradictory statements, one must be false.

Credibility.

There are three ways of destroying the credibility of a witness (1) by assailing his reputation for veracity, and showing through other testimony that he has made different statements at different times; (2) Destroying by proving a different state of facts through different witnesses; (3) by making him contradict himself on cross-examination. The third is the most effective. It obviates all question as to reliability of other witnesses. Lawyers have three purposes in cross-examination: (1) to elicit more truth; (2) to test the witness's truthfulness by endeavoring to confuse him and make him contradict himself; (3) to lay a foundation for impeachment. Whether any of these ends are reached or not depends on the disposition of the witness, and the manner of conducting the examination. Whatever the purpose, a witness is entitled to fair treatment. Judge Walker says1:

"Above all things, let counsel who aim at truth, avoid the manner of examination called brow-beating. There are instances warranting sharp and severe treatment of a witness, but they are rare and exceptional. Courtesy is far more successful than harshness. It pays to consider a witness a gentle

To be of account all new evidence must be in harmony with what is already known in the case. Hence the value of corroborating testimony and of concurrent circumstances. A distinction is to be made here be

1 Modern Jury Trials, 217.

2 See the way in which Erskine sifts the testimony of the witness, Hay, on the trial of Lord George Gordon, Goodrich's British Eloquence, 664.

Circum

tween what is actually known, that is, well-established facts, and what is generally accepted theory. Apparently The apparent discrepancies between new dis- Conflicting coveries and what is thought to be already stances. established, often annoys the most careful scientific investigators. It seemed for a time that one of Pasteur's theories would not conform to what was considered already known:

Pasteur.

"Our tendency to select for observation the details which support our existing theories, is so common that it hardly needs illustration. But that a wrong selection may be made even when our object is to attack a theory, the following example will show. When Pasteur was investigating the causes of splenic fever, he adopted very early in the inquiry the theory of Davaine, that the disease was due to the presence of a certain parasite in the blood, and that consequently the same disease, showing the presence of the same parasite, could be communicated to other animals by inoculation. On the other side, two professors to whom the theory did not commend itself brought forward, as a triumphant refutation of it, what seemed at first a plainly contradictory fact. They had inoculated some rabbits with the blood of an animal which had died of splenic fever, and though the rabbits had died very rapidly no trace of the expected parasite had been found in them either before or after their death. Moreover their blood again had been used to inoculate other rabbits, and these too had died in the same rapid manner, but with the same disregard of what the theory further required. Davaine at once disputed the fact. That is to say, he insisted that the two professors must have used blood which was not properly infected with splenic fever, but with some other disease. The professors, however, were equally certain of their facts; they had got their materials from the best available source, namely, from the director of an establishment where numerous animals which had died of splenic fever were constantly brought. But in order to convince the stubborn theorist they tried the experi

ment again, this time obtaining their materials from the most experienced veterinary surgeon in the neighborhood. Exactly the same result followed, and the facts certainly here appeared to be too strong for the theory.

"It was some years later when the real weakness of the facts themselves came to light. Davaine's theory had meanwhile been enlarged and improved by the discovery that if the blood used for inoculation has already begun to putrefy, the animals inoculated will die by a form of blood-poisoning, quicker in its operation than splenic fever, and too quick to allow the true splenic fever parasites time to multiply. This suggested a new inquiry into the professors' experiments, and it was found that the blood used by them, although certainly taken from cases of splenic fever, had not been sufficiently fresh. So that the fact on which they had relied as contradicting the theory turned out to be wrongly-i.e., incompletely described. Through merely overlooking the detail that the animals whose blood they used had been dead some twenty-four hours, their description of it as 'splenic fever blood' became essentially false."1

Proposition.

The character of the proposition on which evidence is adduced, must modify somewhat its validity. No evidence of any force could be used to show that the universe has always existed in its present Character of state. Testimonial evidence would have little force to sustain what Huxley calls the "Miltonic" theory. Even on what is called the "Evolution" theory there are two classes of evidence between which there seems to be an irreconcilable conflict.

Irreconcila

"I have not the slightest means of guessing whether it took a million of years, or ten millions, or a hundred ble Conflicts. millions, or a thousand millions to give rise to that Huxley. series of changes. A biologist has no means of

1 Sidgwick, Process of Argument, 94.