This is an interesting article suggesting that Mozart's crudeness and odd behavior may have been due to Tourette's. It is written by a present day composer who has the illness. Warning: there are a number of scatalogical references, so you may want to avoid this if you're squeamish about such things.
http://www.telegraph.co.uk/arts/main...ixartleft.html
http://www.telegraph.co.uk/arts/main...ixartleft.html
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