Diogenes Club

The Diogenes Club is a fictional gentleman's club created by Sir Arthur Conan Doyle and featured in several Sherlock Holmes stories, most notably "The Greek Interpreter". It seems to have been named after Diogenes the Cynic (although this is never explained in the original stories) and was co-founded by Sherlock's indolent older brother, Mycroft Holmes.

The club is described by Sherlock Holmes in the stories thus:

"There are many men in London, you know, who, some from shyness, some from misanthropy, have no wish for the company of their fellows. Yet they are not averse to comfortable chairs and the latest periodicals. It is for the convenience of these that the Diogenes Club was started, and it now contains the most unsociable and unclubable men in town. No member is permitted to take the least notice of any other one. Save in the Stranger's Room, no talking is, under any circumstances, allowed, and three offences, if brought to the notice of the committee, render the talker liable to expulsion. My brother was one of the founders, and I have myself found it a very soothing atmosphere."

— The Greek Interpreter

It is described as a place where men can go to read without any distractions, and as such the number one rule is that there is no talking, to the point where club members can be excluded for coughing.