To speak to one person in a company in ambiguous terms, understood by him alone, is as rude as if you had whispered in his ear.
Avoid stale and trite remarks on commonplace subjects; also all egotism and anecdotes of personal adventure and exploit, unless they should be called out by persons you are conversing with.
To make a classical quotation in a mixed company is considered pedantic and out of place, as is also an ostentatious display of your learning.
A gentleman should avoid talking about his business or profession, unless such matters are drawn from him by the person with whom he is conversing. It is in bad taste, particularly, to employ technical or professional terms in general conversation.
Long arguments or heated discussions are apt to be tiresome to others, and should be avoided.
It is considered extremely ill-bred for two persons to whisper in society, or to converse in a language with which all persons are not familiar.
Avoid talking too much, and do not inflict upon your hearers interminably long stories, in which they can have but little interest.
