The one who answers "nothing" when asked "what are you thinking about?" is a worthless individual. We are all thinking about something, generally all of the time. Even while we sleep we think and so we dream. And while we are awake we also dream unlike those who do not think and do not dream.
Our dreams define us. Whithout them we would have no goals to reach. When one sits and thinks they are wrestling with themselves to focus that dream and make it a reality. But those without a thought in their heads wonder about aimlessly, void of ambition.
Then there are those of us refered to as "Dreamers". We are the constant thinkers. Not a moment goes by in which we are not activley advancing our position in the world or enhancing ourselves.
The difference between one of moderate talent and one of supreme excellence is by how much the individual dreams. A great fighter dreams of parries, counters, footwork, attacks, and feigns. A great mathamatician dreams of theorems, algorithms, formulas, and numbers. A great philosopher dreams of meaning, depth, love, and the human condition. A great musician dreams of songs, rhythms, cords, and beats. A great writer dreams of characters, plots, and structure.
A dreamer thinks all the time, especially when nothing is going on: like during commercials, while waiting in line, while eating, while driving, at parties, at sporting events, in movies, and so on. Those who do not dream do not think and therefore time wastes away and they have done nothing to further themselves.
To a dreamer I offer this advise. Surround yourself with those who are constantly thinking and constantly improving upon what they already know; they will only lead you higher. Limit your time with those who minds are empty and whose thoughts are blank; they will only hold you back. To tell the difference just ask, "what are you thinking about?"