"Does Thrasyllus never make mistakes?"

Once again, prophecy provides a link between what we as readers may know, and what Claudius could not yet know by any other means.

Here, Livia tells Claudius that Thrasyllus, an astrologer at the court of Tiberius (mentioned by both Tacitus and Suetonius), has predicted that Caligula will be murdered and that he (Claudius) will be the man to avenge his death.