When a person walks past you in a still environment, there is a sense you can glean in an etherial space which not too many people know about. If the air is still and the person walks past at a calm pace you will first notice a sort of vacuum as they displace the air which your body was occupying. It is as though there were less pressure on your skin and you became lighter. As they continue to walk past, the air continues to move and you are in the vacuum. When they are gone you must be patient and utterly attentive for a moment. You will notice that the displaced aire has followed them and left you in a relative vacuum. You are now standing in the breeze of another human being. I am struck by the wonder of this phenomenon each time it happens. Women and men displace air differently. If you are careful, your right brain might even pick up a scent when the vacuum gets filled. Now you have an impression on your skin and a scent. You are on your way to knowing something about somebody. Sure, you could just talk to them, but who wants to take a chance on that?