If you saw a wild gorilla would you lock eyes, kiss it on the cheek, touch its leg and take a banana from its hands? The exact same rules apply to social situations, we only display our physical movements towards people we know can handle it. These signals are solid keys of truth behind trust. We humans show trust in groups via doing things like sharing eye contact, touching, kissing, dancing, sharing food, drinks and now money.
As for the voice, dynamic social passwords are developed, rehearsed and used in the form of phrases, tonalities and sounds that infer familiarity. This is where the concept of group slang, sounds and noises come into play. Tonalities infer more about a group then meets the ear. They are not just sounds coming from peoples mouths, they are reflections of peoples familiarity within the group. If their use of voice is of similar range as the group it inflects shared respect for each other.
As for language, the type of conversations we have subconsciously indicate levels of trust. The more information we know and intertwine in the conversation the greater inferred trust is implied. People who have an active interest in the other person will remember conversation points of importance, relationships, accomplishments, inside jokes, shared experiences and other personal interests.
So why does it feel so good to receive these signals? I’d love to hear your opinion.