In Aristophanes’ Ranae (907-933) Euripides accuses Aeschylus of deceiving his audience by replacing the logos of his characters with silence. This parody brings up the issue of on-stage silence in tragedy. My article aims to show that: (a) Silence on tragic stage is a technique particular to Aeschylus, who creates strong dramatic effect with his silent characters; silence was an instrument of reaction by which they expressed their tragic condition. (b) Aeschylus paved the way for the introduction of the third actor through this technique, by producing effective dramatic scenes with two speaking actors and a silent one. (c) Both Sophocles and Euripides seem to be conscious of the dramatic and scenic effects of Aeschylus’ technique and manipulate silence to underline dramatic intensity and shift and/or handle the plot of their plays; but silent tragic characters (such as those of Aeschylus) do not appear in their plays.