A problem which is often and justly cited as one to be settled by Eugenics is that presented by the existence among us of the large class of the feeble-minded. No doubt there are some who would regret the disappearance of the feeble-minded from our midst. The philosophies of the Bergsonian type, which to-day prevail so widely, place intuition above reason, and the "pure fool" has sometimes been enshrined and idolized. But we may remember that Eugenics can never prevent absolutely the occurrence of feeble-minded persons, even in the extreme degree of the imbecile and the idiot.[26] They come within the range of variation, by the same right as genius so comes. We cannot, it may be, prevent the occurrence of such persons, but we can prevent them from being the founders of families tending to resemble themselves. And in so doing, it will be agreed by most people, we shall be effecting a task of immense benefit to society and the race. Feeble-mindedness is largely handed on by heredity. It was formerly supposed that idiocy and feeble-mindedness are mainly due to environmental conditions, to the drink, depravity, general disease, or lack of nutrition of the parents, and there is no doubt an element of truth in that view. But serious and frequent as are the results of bad environment and acquired disease in the parentage of the feeble-minded, they do not form the fundamental factor in the production of the feeble-minded.[27] Feeble-mindedness is essentially a germinal variation, belonging to the same large class as all other biological variations, occurring, for the most part, in the first place spontaneously, but strongly tending to be inherited. It thus resembles congenital cataract, deaf-mutism, the susceptibility to tuberculous infection, etc.[28]