The two most characteristic features in the intelligence of the average criminal are at first sight inconsistent. On the one hand he is stupid, inexact, lacking in forethought, astoundingly imprudent. On the other hand he is cunning, hypocritical, delighting in falsehood, even for its own sake, abounding in ruses. These characteristics are fully illustrated in the numerous anecdotal books which have been written concerning crime and criminals. Several attempts have been made to attain accurate figures as to the relative intelligence of criminals, but there must be a considerable element of guess-work in such calculations. Dr. Marro, a reliable observer, detected a notable defect of intelligence in 21 cases out of 500. He found that incendiaries and then murderers yielded the largest proportion of individuals with defective intelligence; then came vagabonds, sexual offenders, those convicted of assault, highwaymen, and those convicted of simple theft. The fraudulent class, as well as pickpockets and burglars, showed no instances of defective intelligence. That is to say that criminals against the person show a much lower level of intelligence than criminals against property. The stupidity and the cunning of the criminal are in reality closely related, and they approximate him to savages and to the lower animals. Like the savage, the criminal is lacking in curiosity, the foundation of science, and one of the very highest acquisitions of the highly-developed man. He is constantly compared in this respect to animals. Macé, a former chief of the Parisian _police de sûreté_, remarks: “In spite of the cunning and tricks, which are too gratuitously credited to thieves, their stupidity generally is scarcely credible; they nearly all resemble the ostrich who, when his head is hidden behind a leaf, thinks that he is not seen because he cannot see.” Dr. Corre remarks: “There is something feline in the criminal: like the cat, indolent and capricious, yet ardent in the pursuit of an aim, the anti-social being knows only how to satisfy his impulsive instincts.” Dr. Wey of Elmira says: “It is a mistake to suppose that the criminal is naturally bright. If bright, it is usually in a narrow line and self-repeating. Like the cunning of the fox, his smartness displays itself in furthering his schemes, and personal gratification and comfort.” “Many criminal illiterates,” he remarks elsewhere, “are so densely stupid as to be unable to tell the right hand from the left.” M. Joly, discussing the criminal’s delight in ruse, adds: “Animals are of all living things fondest of ruse when their special instincts are in action. Idle and untrained children, resolved to deceive their teachers and to amuse themselves at all risks, are more _rusé_ than their comrades at the head of the class. Women make use of ruse much more than men.” I will quote, finally, on this point some words of Dr. A. Krauss[60]:--“The specialists say that criminals are more astute than intelligent.