The Do's and Don't's of Agreeable Conversation : Page 194

The one mistake he will not make is to hang back, to show that he is uncomfortable, to act as if the topic were too deep or farfetched for him to enjoy. This is the unforgivable fault. And it is a fault of which well-meaning, rather bashful people, possibly newcomers to a crowd, are often guilty. The newer you are in a crowd, the more interest you must show in the talk. Often it will be about old times and friends unknown to you. Then it is all the more important that you pay the most interested attention, leaning forward, rather than hanging back, so that you will soon be initiated in the "secrets" of the set. You must show so much interest that the others will not be made to realize self-consciously that what they talked about might not have been interesting to you. Because the talk of a new set is often about unknown personalities, a shy or modest person almost feels as if he were eavesdropping on confidential matter. But once he is in the crowd, he must not feel that way, If it is a general conversation, he must have his eyes follow every speaker keenly.