There is a lot if swearing in the silent What Price Glory if you can read lips (the card titles cleans the language up).
There may be a lot of swearing in that Lon Chaney film where he plays the Marine sergeant, and what does the bad guy
really say to
The Virginian in the silent version of the film to illicit the card title response, "Smile when you say that"? But who watches a silent film to read lips??? No offense, but I've never before known anyone who claimed to read lips in silent movies. Sounds like a college drinking game!
However, my original point is not whether or not actors ever cussed on screen in silent films but rather that the vast majority of movie-goers didn't know what they were saying and, more importantly, didn't
need to know what they were saying to enjoy the film. That's one reason why Chaplin's films were hits all over the world. Just edit in a few card titles in the local language and he was good to go.
For that matter, there may be all sorts of nasty language in the Japanese print of
Seven Samurai or the original German version of
Das Boot or the French
Wages of Fear. But if there is, it blows past me since I'm not fluent in any of those languages. As a result, whether or not the obscenity makes the film more "realistic" in its native tongue, not understanding what is said doesn't distract from my enjoyment of the film.
As for silent movies, the big draw was always the acting one could see on the screen, not the dialogue one couldn't hear. For all I know, Lillian Gish may be cussing a blue streak while running across those ice flows or reciting the Lord's Prayer or composing a shopping list. Point being, what she's actually
saying doesn't mean a damn thing one way or another--it's what she portrays through her
acting that carries the story along!