This power of the will over the thoughts is one in which men differ enormously. Thus--to take the most familiar instance--the capacity for worry, with all the exaggerations and distortions of sentiment it implies, is very evidently a constitutional thing, and where it exists to a high degree neither reason nor will can effectually cure it. Such a man may have the clearest possible intellectual perception of its uselessness and its folly. Yet it will often banish sleep from his pillow, follow him with an habitual depression in all the walks of life, and make his measure of happiness much less than that of others who with far less propitious circumstances are endued by nature with the gift of lightly throwing off the past and looking forward with a sanguine and cheerful spirit to the future. It is hardly possible to exaggerate the different degrees of suffering the same trouble will produce in different men, and it is probable that the happiness of a life depends much less on the amount of pleasurable or painful things that are encountered, than upon the turn of thought which dwells chiefly on one or on the other. It is very evident that buoyancy of temperament is not a thing that increases with civilisation or education. It is mainly physical. It is greatly influenced by climate and by health, and where no very clear explanation of this kind can be given it is a thing in which different nations differ greatly. Few good observers will deny that persistent and concentrated will is more common in Great Britain than in Ireland, but that the gift of a buoyant temperament is more common among Irishmen than among Englishmen. Yet it co-exists in the national character with a strong vein of very genuine melancholy, and it is often accompanied by keen sensitiveness to suffering. This combination is a very common one. Every one who has often stood by a deathbed knows how frequently it will be found that the mourner who is utterly prostrated by grief, and whose tears flow in torrents, casts off her grief much more completely and much sooner than one whose tears refuse to flow and who never for a moment loses her self-command.