The difference between the first stage, concentration, and the second stage, meditation, is like the difference between a still photograph and a cinema film. In the first stage, you centre your attention upon an object, just to note what it is, in its details, parts, and qualities, whereas in the second stage, you go on to think all around and about the object in its functional state. In concentration, you merely observe the object; in meditation, you reflect upon it. The difference between meditation and ordinary thinking is that ordinary thinking does not go beyond its own level nor intend to stop itself, whereas meditation seeks to issue forth on an intuitional and ecstatic level whereon the thinking process will itself cease to function.
-- Notebooks Category 4: Elementary Meditation > Chapter 4: Meditative Thinking > # 29