332 THE POPULAR SCIENCE MONTHLY, 



established phenomena of an old one ; the passing from death into life 

 is to be received with as little question as the passing from life into 

 death. Under this feature of current logic delusionists of all kinds have 

 consistently and persistently found refuge. 



The different classes of claims in regard to real or alleged phenom- 

 ena, in their relation to the quality and quantity of evidence needed to 

 prove them, may be thus presented in order of climax : 



1. Claims as to unsystematized knowledge or matters of every -day 

 life. 



Under this head comes most of the testimony commonly given in 

 courts of justice. For claims of this kind experts are not usually re- 

 quired, and the mistakes which are constantly made, every hour and 

 every moment, are of comjDaratively trifling account, since they affect 

 individuals and not general principles. 



It is one of the innumerable proofs of the limitations of the human 

 brain, that the rules of evidence in our courts of justice, although prac- 

 tically, on the average, as good, with some exceptions, as can be expected 

 for the obtaining of legal justice, necessarily imperfect and uncertain, 

 are yet, in many respects, to the last degree unscientific. The exclu- 

 sion, for example, of hearsay testimony, and of the testimony of a wife 

 against her husband, and the modes of questioning and cross-question- 

 ing of witnesses make it oftentimes impossible to obtain justice. The 

 scientific man, desirous not of gaining a point but of ascertaining the 

 truth, and recognizing the untrustworthiness or uncertainty of nearly 

 all human testimony, would in many cases prefer hearsay to direct 

 statements, and would give more for the evidence of a near relation or 

 a wife than for that of all the world besides. 



One needs but to follow the details of a few great causes, as the Mc- 

 Farland trial, the Beecher-Tilton, the Tichborne, and the Vanderbilt 

 cases, to see that by the rules of evidence, or at least by the actual 

 practice of courts, testimony which scientifically is valueless is admitted, 

 while the only testimony that is, or promises to be, of any scientific 

 value is systematically excluded. 



The great advances in science have not been made in courts of jus- 

 tice. Even when on questions of science experts are called to testify, 

 their testimony is obtained in such a way as to impair, if not destroy, 

 its value, and to obscure more than to reveal the truth. 



From the scientific point of view, a legal trial is really an experiment 

 with living human beings, and, like all experiments of that kind, is liable 

 to six sources of error, all of which must be guarded against if we are 

 to find the exact truth. The science and art of experimenting with 

 living human beings are not yet understood, even by physiology and 

 pathology, to which department they belong. 1 



1 That the art of experimenting with living human beings is now but in its early child- 

 hood is shown by the fact that all those who give special attention to the physiology 



