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76 its gradations, with exquisite nicety, in one of the chapters of his The History of Rasselas, Prince of Abyssinia. But there is surely a clear distinction between a disorder which affects only the imagination and spirits, while the judgement is sound, and a disorder by which the judgement itself is impaired. This distinction was made to me by the late Professor Gaubius of Leyden, physician to the Prince of Orange, in a conversation which I had with him several years ago, and he expanded it thus: 'If (said he) a man tells me that he is grievously disturbed, for that he imagines he sees a ruffian coming against him with a drawn sword, though at the same time he is conscious it is a delusion, I pronounce him to have a disordered imagination; but if a man tells me that he sees this, and inconsternation calls to me to look at it, I pronounce him to be mad.' It is a common effect of low spirits or melancholy, to make those who are afflicted with it imagine that they are actually suffering those evils which happen to be most strongly presented to their minds. Some have fancied themselves to be deprived of the use of their limbs, some to labour under acute diseases, others to be in extreme poverty; when, in truth, there was not the least reality in any of the suppositions; so that when the vapours were dispelled, they were convinced of the delusion. To Johnson, whose supreme enjoyment was the exercise of his reason, the disturbance or obscuration of that faculty was the evil most to be dreaded. Insanity, therefore, was the object

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