One of the saddest things an instructor has to do on occasion is to cite a student for plagiarism. This is a form of plagiarism in the speech setting.
Plagiarism includes more, too, than simply undocumented verbatim quotation.
So, for example, if you paraphrase a movie review from Newsweek without acknowledging that David Ansen had those insights, you're guilty of plagiarism. I can see what he means. Perhaps this is because the architect, Sir John Vanbrugh, although a man of genius, was really an amateur. Country estates were built essentially by amateurs such as Sir John Vanbrugh, who built the splendid Blenheim Palace for General Marlborough. Voltaire didn't like war and he didn't like Blenheim, which he called a great heap of stone without charm or taste.