The illness emphasised certain traits in his character. He argued cuttingly, his biting satire did not shrink at insults, and his expressions could be rude and cruel. Though in general Marx had blind faith in his closest friends, nevertheless he himself complained that he was sometimes too mistrustful and unjust even to them. His verdicts, not only about enemies but even about friends, were sometimes so harsh that even less sensitive people would take offence ... There must have been few whom he did not criticize like this ... not even Engels was an exception.