Oh yes, Bergman's Tystnaden and Melville's Les Enfants Terribles are something I always kept in the same box. They both don't show explicit incestuous or sexual imagery, though Bergman gave some shy attempts. It's about fraternal attraction subtly elaborated on both sides. Emotions sparkle in the air causing grievances and hard feelings, but never revealing themselves in actual physicalities. Anyhoo, Bergman had to put up with much trouble fighting censoring boards. What's funny, both ticklish scenes in Tystnaden didn't contain incestuous sex at all. Gee, couldn't even imagine the loss World Cinema would have to put up with if French were Protestant society!

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At the same time, each of the two processes (I'd say) even stronger points (besides incest). Enfants are rather timid concerning sexuality in French cinematic tradition, but they openly speak of horrors rampant teenagers could wreak upon themselves. It's a sort of pre-hippie posh flower-power community that finds it sexy brandishing guns in order to solve issues. On the other side, Tystnaden deals a lot with an individual's (Ester's) fear of death. Both incestuous parties are grown up here.
All in all, two nice studies with a shared interest coming from two different traditions and agendas.