To Know someone is no different than concentrating upon loved ones, friends, associations and even the creatures of the fields. In fact, any concentration brings up all that one has known and loved.
The speechless are those who silently observe all of the above; there is no time and space that can exclude such beloved memories. The real question is--do you conmingle with those whom you know and have known? I visit others often, and likewise they often visit me, like when I am dreaming, or consciously contemplating their presence. It is no hard practice to associate with others. It's as easy as breathing.
How one "interprets" these practices clearly indicates how much and how far one goes to socialize with known people, in or out of the brain. It is called "commmon sense".
The virtue of a highly evolved being embraces all people and things and dispels the darkness which isolates them.
Hua Hu Ching-primary lesson.