Some authors deny that political revolutions have their causes in economic conditions. Lombroso and Laschi, for example, attempt to explain them chiefly by physical influences; which is the more astonishing, because in the general opinion it is from economic causes that they are derived. They adduce, among other things, to support their opinion, the fact that out of 147 revolts that took place in Europe between 1793 and 1880, only a third were attributable to economic conditions. It goes without saying that this does not at all prove the correctness of their thesis, since in all these cases the authors are speaking only of direct causes, while most military revolutions, revolts against the royal power, etc., spring from economic conditions, even if indirectly. It is true that in the 19th century the direct revolutionary influence of crises and famines has decreased, because of the measures taken by the governments. This does not however prevent there having been revolts occasioned by such conditions (Lyons in 1831, etc.). The frequent revolts in Belgium and France, rich countries, do not furnish any proof against the thesis of Dr. Colajanni; for notwithstanding the great wealth of these countries, nothing proves that it is equally divided. As soon as the poverty of a people has passed certain limits, we see in that country neither crimes, revolutions, nor suicides, since all energy is then extinct. Another question is this: how far is there a correlation between the progress made by socialism and the increase of criminality. [238] Several authors, like Garofalo, are of the opinion that there is an intimate connection between the two. But they do not furnish any facts as proofs in support of their assertion, to which, on the contrary, the facts give the lie. The countries where socialism is most widely spread do not show the greatest criminality; rather the contrary. The German and Italian districts where there are the most socialists are no longer the most criminal. How could it be otherwise? While socialism is the conscious and collective reaction against the existing order, crime is the unconscious and individual reaction against that order. Next, Dr. Colajanni turns his attention to idleness and vagrancy, which are both causes of crime. Out of 32,943 thefts in Paris in 1882, 57% were committed by vagrants.