Though diffusely written, and neither brilliant nor profound, Crusius' philosophical books had a great but shortlived popularity.
He could very easily write in different styles at different times, now avoiding hiatus and now not, sometimes writing diffusely and sometimes briefly, partly polishing and partly leaving in the rough, according to the subject, his own state of health or humour, his age, and the degree to which he had developed a given topic; and all this even in the same manuscript as well as in different manuscripts, so that a difference of style between different parts of a work or between different works, explicable by one being earlier than another, does not prove either to be not genuine.
He writes more wordily and diffusely.
The virus affects the brain diffusely, but seems to particularly involve the cerebellum, producing problems with balance, coordination and speech.