"Think about this scenario: You see someone at a party you like; his social profile is immediately projected onto your retina–great, a 92% match. By staring at him for two seconds, you trigger a pairing protocol. He knows you want to pair, because you are now glowing slightly red in his retina screen. Then you slide your tongue over your left incisor and press gently. This makes his left incisor tingle slightly. He responds by touching it. The pairing protocol is completed."