Characteristic of consciousness...

The king asked: "Venerable Nagasena, what is the distinguishing characteristic of consciousness?"

"The distinguishing characteristic of consciousness, your majesty, is cognizing."

"Give me an analogy."

"Just as, your majesty, a city-superintendent sitting at the crossroads in the middle of the city could see a person coming from the eastern direction, could see a person coming from the southern direction, could see a person coming from the western direction, and could see a person coming from the northern direction, then indeed, your majesty, does a person cognize with consciousness a form he sees with the eye, cognize with consciousness a sound he hears with the ear, cognize with consciousness a scent he smells with the nose, cognize with consciousness a taste he savors with the tongue, cognize with consciousness a touch he feels with the body, and cognize with consciousness a mental state he cognizes with the mind. Indeed thus, your majesty, the distinguishing characteristic of consciousness is cognizing."

"You are clever, venerable Nagasena."

http://www.accesstoinsight.org/tipitaka/kn/miln/miln.2x.kell.html#miln-2-3-08-cymbals