The mental state is of progressive impairment. The ideas flow slowly, and there is slowness or hesitation in speech in giving utterance to them, even to the degree of amnesic aphasia. Word-blindness occurs, and word-deafness and the various disturbances of speech associated with the several forms of aphasia. After the dementia is very marked there is often a most extraordinary variation in it. The patient may be confused, incoherent, and to appearance hardly capable of sustained thought, but soon quite able to perform a business transaction. The friends say of such patients, “He is crazy to-day,” or “To-day he is sane;” and this quite independent of the marked increase in the dementia which occurs from organic changes, epileptiform and apoplectiform attacks, after which the advance in the mental impairment is rapid and great. Accompanying dizzy and congestive attacks there is a temporary dementia which may be over in an hour or two. {192} The patient may recall many long-past events fairly well when he cannot find his way to the dinner-table without blundering, when he does not know morning from afternoon, and after he is unable to dress and undress himself without constant remindings or even actual help. Such paralytics wander off and die of exposure, are picked up by the police as having lost their way or as not knowing where their home is, or fall into some fatal danger from which they have not mind enough to extricate themselves. When the mental impairment has reached this point the lack of mind shows itself in a lack of facial expression, which is so characteristic of the disease that with a practised eye it is recognized as far as the countenance can be distinctly seen; and from this point the progress is commonly quite rapid to absolute dementia, entire inability to form or express thoughts, too little intellect to even attend to the daily natural wants, and a descent to the lowest possible plane of vegetative life, and then death.