SECTION 13. In all matters affecting our weal or woe, we should be careful not to let our imagination run away with us, and build no castles in the air. In the first place, they are expensive to build, because we have to pull them down again immediately, and that is a source of grief. We should be still more on our guard against distressing our hearts by depicting possible misfortunes. If these were misfortunes of a purely imaginary kind, or very remote and unlikely, we should at once see, on awaking from our dream, that the whole thing was mere illusion; we should rejoice all the more in a reality better than our dreams, or at most, be warned against misfortunes which, though very remote, were still possible. These, however, are not the sort of playthings in which imagination delights; it is only in idle hours that we build castles in the air, and they are always of a pleasing description. The matter which goes to form gloomy dreams are mischances which to some extent really threaten us, though it be from some distance; imagination makes us look larger and nearer and more terrible than they are in reality. This is a kind of dream which cannot be so readily shaken off on awaking as a pleasant one; for a pleasant dream is soon dispelled by reality, leaving, at most, a feeble hope lying in the lap of possibility. Once we have abandoned ourselves to a fit of the blues, visions are conjured up which do not so easily vanish again; for it is always just possible that the visions may be realized. But we are not always able to estimate the exact degree of possibility: possibility may easily pass into probability; and thus we deliver ourselves up to torture. Therefore we should be careful not to be over-anxious on any matter affecting our weal or our woe, not to carry our anxiety to unreasonable or injudicious limits; but coolly and dispassionately to deliberate upon the matter, as though it were an abstract question which did not touch us in particular. We should give no play to imagination here; for imagination is not judgment--it only conjures up visions, inducing an unprofitable and often very painful mood.