As in animal, so in mental life, there are gormandizing and gluttony, tending always to paralysis of voluntary effort. The devouring of facts, as they are found both in nature and in books, indulgence in social pleasures immoderately and constantly, pietism that feeds exclusively upon the things of religion, the feasting of the imagination upon the creations of fiction--all these are debilitating; and a blessed thing to the world is it that they unfit the mind for writing at all, as the overfeeding of the body unfits its organs for labor. Plethoric minds do not trouble the world with books, or with conversation, or with preaching. Activity simply demands food enough, and in sufficient variety, to feed its powers while operative, from day to day. This is the reason why immensely learned men have rarely done much for the world. Many of them have won reputations, like remarkably fat steers, for breadth of back and depth of brisket, but they are never known to move more than their own enormous bulks. Beyond a certain point of mental feeding, over and above the necessities of labor, the mind gets sleepy and clumsy. I have alluded to authors, particularly, because, unlike the world in general, they give form and record to their life. The masses of men live as authors live, but their lives are not put down in books, so that the public may read and measure them. We will suppose that two men are fed upon the same diet. Each shall have sufficient food for his religious, social, esthetic, domestic, sensational, and emotional natures, yet only one of them shall embody in books the life which he draws from these varieties of nourishment. The other lives essentially the same life, but it fails of record. It may be as rich, and characteristic, in every particular, as that of the author, but it fails of artistic form because, perhaps, he lacks the peculiar mental gift required for its construction. So the real life of the author and the life of his reader may be the same, the one having advantage over the other in no particular, and the fact that one is embodied in artistic forms conferring upon it no essential excellence. What I have said about authors, therefore, applies to all mankind, engaged in whatever calling or profession. If any portion of any man's nature be not well fed, he will betray the fact in his life. Poverty of food in any particular will surely bring poverty of manifestation in that department of life which is deprived of its natural nourishment.