We all belong to many in-groups. As a result, our self-identification shifts from situation to situation. Putting other people into categories affects our assessment of them. Putting ourselves into in- and out-group categories also has an effect – on the way we see our own place in the world and how we view others.

Psychologists have found that there is no minimal requirement necessary for a person to feel a kinship with an in-group. It is not necessary for you to share any attitudes or traits with your fellow group members, or even for you to have met the other group members. It is the simple act of knowing that you belong to a group that triggers your in-group affinity.

The human brain has evolved to be very efficient at pattern recognition, but as the confirmation bias shows, we are focused on finding and confirming patterns rather than minimizing our false conclusions. We should learn to spend as much time looking for evidence that we’re wrong as we spend searching for reasons we are correct.

How strong an influence does a person’s appearance have on us? I don’t mean beauty – I mean something more subtle, a look of intelligence, or sophistication, or competence…They imply that before anyone even discusses the issues, the race may be over, since looks alone give a candidate a huge head start. With all of the important issues of the day, it’s hard to accept that a person’s face would really sway our vote.

In modern human society, there are two kinds of dominance: Physical and Social. Physical dominance is based on aggression or the threat of aggression. Social dominance is based on admiration rather than fear and is acquired through social accomplishment rather than physical prowess.

If two speakers utter exactly the same words but one speaks a little faster and louder and with fewer pauses and greater variation in volume, that speaker will be judged to be more energetic, knowledgable, and intelligent. Expressive speech, with modulation in pitch and volume and with the minimum of noticeable pauses, boosts credibility and enhances the impression of intelligence.

While our conscious minds are busy thinking about the meaning of words people utter, our unconscious is busy judging the speaker by other criteria, and the human voice connects with a receiver deep within the human brain. To the unconscious minds, voice is very important. Consumers pick up a great many sophisticated signals from the tone and quality of a person’s voice and from the cadence.