Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
@ACL - I see that I hadn't answered your comment. Sorry! I don't remember the details, but I was referring to a paragraph on p. 38 of Weil's book on topological groups. I added a screenshot of the paragraph to the question. I'm afraid I overstated Weil's comment.
@lambda - Thanks a lot! Looks very interesting! If I understand correctly you're saying that if $C$ is a maximal chain in a boolean lattice, then $C$ isn't fixed by any nontrivial automorphism. Could you give me an argument or a reference?